Note: This analysis of Deoxys will be a composite of almost every media it has appeared in minus the trading card game, similar to my Mewtwo analysis. However, this will also not include the Pokémon arcade games. Also like said analysis, moves used by Deoxys that it doesn’t normally learn will be included due to both being a Legendary Pokémon and wild Deoxys having used unnatural moves in the past. Sources for where it uses those moves will be given, and items and moves specific to events will not be included.
Sources:
Mainline Pokémon games
Pokémon Movie: Destiny Deoxys
Pokémon anime (AG171, AG172, DP112, PK21, SM124)
Pokémon Adventures manga (PS269-PS302, PAORAS00-PAORAS21)
Pokémon Generations (Episode 9: The Scoop)
Pokémon Diamond and Pearl Adventure! manga (DPAS1, DPAS2)
Pokémon Mystery Dungeon series
Pokémon Ranger series
Pokémon Ranger the Comic: Double Mission
PokéPark Wii: Pikachu’s Adventure
Pokémon GO
Super Smash Bros. series
Background
Deoxys is a Psychic-type Mythical Pokémon who started as nothing more than the DNA of an extraterrestrial virus. This virus was traveling on a meteor through space until at some point, it was exposed to a laser beam. This exposure caused the virus to mutate until it formed into the form Deoxys has today. It’s also thanks to all of this that Deoxys is very intelligent and able to shapeshift its body into the different Formes it’s known for.
Two Deoxys in particular arrived on Earth, though one had been stuck in its crystalline form. Before the active Deoxys was able to restore its friend though, it was attacked by the Sky High Pokémon, Rayquaza. The battle ended with this Deoxys also losing its body, and it wouldn’t be able to search for its friend for another four years.
After those four years, Deoxys had fully regenerated itself, but its friend had not. It traveled to LaRousse City and kept creating auroras, hoping the other Deoxys would come, as it knew its friend was in the city. However, the constant auroras Deoxys kept making disturbed Rayquaza, who tracked down Deoxys and attacked it again. As the two battled, the other Deoxys had finally regenerated itself with the help of the city's technology and stopped the battle between the two. Together at last, the two returned to space peacefully... after tag teaming Rayquaza and almost dying from the robot cube apocalypse.
More Info
Height: 5’07” | 170.2 cm
Weight: 134.0 lbs. | 60.8 kg
Type: Psychic
Classification: DNA Pokémon
Named by Professor Lund
The crystal on its chest is actually its brain
Travels via meteor
Has an eternal bromance with Rayquaza
Equipment
Revive Robe
An exclusive item to Deoxys.
When equipped, it forces its opponents to exert double the amount of energy needed when attacking or using their powers.
Doesn’t mean they do more damage, just that it takes more effort for the same result.
Makes opponents feel fatigued much more quickly than they usually would.
Powers & Abilities
Moveset
Deoxys has a wide variety of physical, special, and status moves at its disposal. The effectiveness of these moves is mainly determined by the Forme it takes, as they each obviously have different stats. That said, Deoxys’s Attack and Special Attack are both equal no matter the Forme, meaning it’s great at striking both up close and far away with its attacking moves. Also, due to Deoxys being a Psychic-type Pokémon, its Psychic-type attacks deal 50% more damage. The following is a list of all the moves Deoxys can use:
Leer: A Normal-type status move. Deoxys gives off an intimidating leer that lowers the Defense of all of its opponents.
Wrap: A base 15 power Normal-type physical move. Deoxys wraps its tentacles around its opponent and squeezes them. It will do this for an extended period of time to keep them trapped and deal more damage.
Night Shade: A Ghost-type special move. Deoxys makes its opponent see a frightening mirage, damaging them equal to its level, which at maximum potential would be 100. It can also be used to launch dark beams that shock from the crystal on Deoxys’s chest at opponents (1:19:48/1:22:20), which can even be shot out omnidirectionally. This omnidirectional blast can also be rotated around itself.
Teleport: A Psychic-type status move. Deoxys teleports to another location, whether that would be to go to far away destinations in less than a second, escape from rough battles, dodge attacks, or maneuver itself around while in combat.
Double Team: A Normal-type status move. Deoxys moves rapidly to create illusory copies of itself to raise its evasiveness and trick its opponent. These copies can actually damage those who touch them, giving them another use if its opponent tries to physically attack the fake Deoxys.
Knock Off: A base 65 power Dark-type physical move. Deoxys slaps down its opponent’s items and equipment so they can’t use it. If something is knocked off, this move’s power is boosted by 50%.
Taunt: A Dark-type status move. Deoxys taunts its opponent, forcing them into a rage that makes them only able to use attacking moves instead of status or other supportive moves.
Pursuit: A base 40 power Dark-type physical move. Deoxys quickly strikes its opponent. If they were going to try to escape from battle, this move briefly prevents them from doing so, doubles in power, and can’t miss. It can also be used to create a counter that reflects the exact amount of damage Deoxys takes back to the opponent so long as that attack doesn’t defeat it.
Spikes: A Ground-type status move. Deoxys lays a trap of caltrops beneath its opponent’s feet, damaging them if they step on them. It can set up multiple layers of caltrops to deal more consistent damage and cover more area.
Psychic: A base 90 power Psychic-type special move. Deoxys attacks its opponent with a powerful telekinetic force, which has a 10% chance of lowering their Special Defense. It can also be used to pick up objects to use for various offensive or defensive purposes (1:19:08/1:19:19) or control others’ movements to throw them around or allow them to fly alongside it (1:17:41 and 19:57).
Snatch: A Dark-type status move. Deoxys prepares itself, and if its opponent uses a beneficial status move, such as ones that increase stats, restore HP, etc., it will prevent them from performing it and steal its use for itself. This move has much higher priority compared to most other moves, meaning Deoxys will almost always be able to steal its opponent’s status move.
Superpower: A base 120 power Fighting-type physical move. Deoxys strikes its opponent with great power. While a powerful up-close attack, when it lands, it lowers Deoxys’s Attack and Defense.
Swift: A base 60 power Normal-type special move. Deoxys creates and launches out multiple yellow star projectiles that never miss its opponents. When it hits multiple opponents, its power slightly weakens.
Psycho Shift: A Psychic-type status move. Deoxys uses its psychic power of suggestion to transfer any status effects it has to its opponent. Of course, this means Deoxys is cured from its status effect.
Zen Headbutt: A base 80 power Psychic-type physical move. Deoxys focuses its willpower to its head and headbutts its opponent, which has a 20% chance of flinching them.
Cosmic Power: A Psychic-type status move. Deoxys absorbs a mystical power from space to raise its Defense and Special Defense.
Iron Defense: A Steel-type status move. Deoxys hardens its body’s surface like armor to sharply raise its Defense.
Amnesia: A Psychic-type status move. Deoxysis temporarily empties its mind to forget its concerns to sharply raise its Special Defense.
Agility: A Psychic-type status move. Deoxys relaxes and lightens its body to sharply raise its Speed. This can also affect allies like its clones.
Recover: A Normal-type status move. Deoxys creates an energy aura around itself that restores its cells, which restores 50% of its maximum HP. The restorative power can aid Deoxys when there are disturbances in the geomagnetic waves (18:04), though it may need help to pull this off if it’s too out of control (17:56). This can even regenerate its crystal brain should it be damaged.
Zap Cannon: A base 120 power Electric-type special move. Deoxys fires forward an electric orb like a cannon that damages its opponent while also always paralyzing them.
Hyper Beam: A base 150 power Normal-type special move. Deoxys charges up and fires a powerful beam of energy at its opponent, though after using it, it is left vulnerable and can’t use other moves for a short while. This beam can be continuous for a long while.
Counter: A Fighting-type physical move. Deoxys takes a counter stance and allows itself to be attacked by its opponent. If it’s hit physically, it will then retaliate back at them, dealing twice the amount of damage it took.
Mirror Coat: A Psychic-type special move. Deoxys coats itself in psychic energy and allows itself to be attacked by its opponent. If it’s hit specially, it will then retaliate back at them, dealing twice the amount of damage it took.
Extreme Speed: A base 80 power Normal-type physical move. Deoxys charges at the target at blinding speed and strikes them. This move has much higher priority compared to most other moves.
Protect: A Normal-type status move. Deoxys forms a forcefield that protects it from all kinds of attacks and status moves. This can linger for a bit to allow it to attack opponents while protected. However, while the first time it’s used is guaranteed to work out perfectly fine, if it’s used multiple times in a row, it becomes more and more likely to fail the more it successfully protects Deoxys. Though, it can attack while protecting itself and hurt those who make contact with its forcefield. This can also be used to protect Deoxys from things that are trying to emotionally control it (14:26). The forcefield itself can even be expanded wide enough to cover an entire city while staying up for a whole day (48:56). This also means those inside won’t be able to escape. However, damaging Deoxys enough will cause the forcefield to disappear (1:18:26).
Safeguard: A Normal-type status move. Deoxys creates a protective field around itself and any allies that prevents them from being inflicted with status effects. However, this won’t remove any status effects they have before it’s used. This can also be used to form massive protective barriers that keep those inside stuck while preventing outsiders from coming in (18:04/18:12).
Reflect: A Psychic-type status move. Deoxys puts up a wondrous wall of light, which reduces the damage taken from physical attacks by half for a while. This also affects any allies at the cost of only decreasing special damage by a third instead of by half. It can also be used to form a forcefield around itself for protection. Used in the Pokémon Adventures manga and Pokémon Generations.
Light Screen: A Psychic-type status move. Deoxys puts up a wondrous wall of light, which reduces the damage taken from special attacks by half for a while. This also affects any allies at the cost of only decreasing special damage by a third instead of by half. Used in the Pokémon Adventures manga.
Skill Swap: A Psychic-type status move. Deoxys employs its psychic power to exchange passive Abilities with its opponent. Used in the Pokémon Adventures manga.
Meteor Mash: A base 90 power Steel-type physical move. Deoxys hits its opponent with a hard punch fired like a meteor, which has a 20% chance of raising its Attack if it hits. Used Pokémon Ranger: Guardian Signs when transferred over to the main games.
Detect: A Fighting-type status move. Deoxys enables itself to predict its opponents moves and avoids them, both attacks and status moves. This can linger for a bit to allow it to attack opponents while protected. However, while the first time it’s used is guaranteed to work out perfectly fine, if it’s used multiple times in a row, it becomes more and more likely to fail the more it successfully defends Deoxys. Used Pokémon Ranger: Guardian Signs when transferred over to the main games.
Shadow Ball: A base 80 power Ghost-type special move. Deoxys creates and launches a ball of ghostly energy at its opponent, which has a 10% chance of lowering their Special Defense. This can also be used to fire out a large but slow moving projectile that hovers around instead of being launched straight forward as usual. Used in Pokémon Ranger and Pokémon Generations Episode 9: The Scoop.
Charge Beam: A base 50 power Electric-type special move. Deoxys blasts a charge of electricity at its opponent, which has a 70% chance of raising its Special Attack if it hits. Used in Pokémon GO.
Thunderbolt: A base 90 power Electric-type special move. Deoxys fires a bolt of electricity that crashes down on its opponent, which has a 10% chance of paralyzing them. Used in Pokémon GO.
Poison Jab: A base 80 power Poison-type physical move. Deoxys jabs its opponent with either its tentacle or arm steeped in poison, which has a 30% chance of poisoning them. Used in Pokémon GO.
Dark Pulse: A base 80 power Dark-type special move. Deoxys releases a horrible aura imbued with dark thoughts at its opponent, which has a 20% chance of flinching them. Used in Pokémon GO.
Rock Slide: A base 75 power Rock-type physical move. Deoxys hurls multiple large boulders at its opponents, which has a 30% chance of flinching each of them. When it hits multiple opponents, its power slightly weakens. Used in Pokémon GO.
Calm Mind: A Psychic-type status move. Deoxys quietly focuses its mind and calms its spirit to raise its Special Attack and Special Defense. Used in Pokémon Mystery Dungeon: Rescue Team DX.
Psycho Boost: A base 140 power Psychic-type special move. This is Deoxys’s signature move and its most powerful one at that. It forms a multi-colored psychic ball of energy between its tentacles before firing it off at its opponent for a full power attack. These can even be fired rapidly, spread shotted, both, or launched all around itself. It can also be used to create an enormous explosion of psychic energy that hits all around Deoxys. However, if it lands, this does harshly lower Deoxys’s Special Attack.
Pressure
Deoxys’s passive Ability that’s active at all times.
Forces opponents to exert double the power that they would normally be using in their attacks.
Like the Revive Robe, this doesn’t make their attacks any stronger, but makes them take more effort for the same result.
These can stack with each other, making the opponent use triple the amount of energy usually needed when battling.
Flight
Through psychic powers, Deoxys possesses unrestricted flight that allows it to soar through the air at incredibly high speeds (19:51).
Can even fly through outer space.
Deoxys’s brain, should its body be destroyed, also has limited levitation so long as it has enough energy (11:43).
Aurora Creation
Deoxys has the ability to produce auroras from the crystal brain in its chest (0:53), done so by creating geomagnetic waves (3:39).
Meaning it can disrupt machinery (1:27/5:30), interrupt network signals, and affect others who need the use of geomagnetic fields (1:01/3:50).
Usually used so it can communicate with other Deoxys by giving off electromagnetic wavelengths (1:03:38/1:20:37).
Can travel around in spirit via a small malleable and intangible aurora if it’s reduced to its crystal (30:48/32:14/44:33/1:02:53), which can be seen as its aurora before it would normally expand (1:17:04).
Can deceive others into thinking it is in a different Forme.
Can create auroras even in other dimensions it's currently not in (0:53/4:41).
Electromagnetic Sight
Deoxys’s vision is a little different from a normal Pokémon’s (1:04:17).
It sees the world through the use of electrical fields (9:47/36:34), allowing it to see through objects (7:21/1:20:12/1:21:27).
Useful for sneak attacks or intel in conditions where its opponent can’t see Deoxys (9:08).
Telepathy
Deoxys can telepathically communicate with others through images of its past (19:17).
Regeneration
Deoxys is able to almost instantly regenerate its body if it’s been severely damaged in battle (8:43).
So long as its brain remains intact, it can restore its whole body if it’s been obliterated after a few years (11:24/15:00/54:46).
Technology Manipulation
Deoxys can control technology with its psychic powers.
Can use this to list words on the screens of electronic devices for it to better communicate with others.
Able to launch an electromagnetic beam from its face, which is related to its own electromagnetic sight (1:20:12), that’ll cause technology to malfunction (36:48/45/43).
Duplication
Also called Deoxys Divide, Deoxys is able to clone itself.
These can range from a few to several dozen all at once (48:24).
They’re capable of using Pokémon moves and Abilities themselves, including Double Team funnily enough.
They follow its orders while still being able to be far away from the original Deoxys (59:08).
Are very capable of overwhelming an opponent (1:04:43).
Whether they’re normal clones or mirages depends on the continuity, but they are both physical in form, being able to take damage or be defeated (50:40).
This does mean they can be used for protection, though they’re weaker than the original.
They can appear in Deoxys’s various Formes.
Mind Control
Deoxys can mind control others with its psychic powers (18:31).
Can speak through them (18:44/19:11).
Those under its control don’t remember what happened (4:10).
Portal Creation
Deoxys can form portals to other dimensions (4:41).
Can take others through them as well (20:14).
Certain portals can even drag others into them like a black hole to force others into different locations.
Can lead to its own personal world (3:58/4:17), though these can also lead to other locations.
Can be used to view the location of its choosing (6:49).
Though others will also be able to see Deoxys and its location unless they’re unaware that the portal is there (9:50/12:46).
Dimension Creation
Deoxys is able to create dimensions that it can use its portals to enter (4:41 and 10:02).
Its personal one is described as its room (4:57).
Its dimension has zero gravity and objects that bounce others around (4:01/16:37).
Absorption
Deoxys is able to absorb the energy found within meteors into its brain to increase its stamina and power (17:44/18:21).
Enough energy can even regenerate its entire body if it was destroyed and left with only its brain (14:29/17:08).
Being the DNA Pokémon, it’s also capable of absorbing blood.
Magnetism
Deoxys can create a magnetic field that attracts metallic objects towards it (18:04/18:21).
This also makes compasses and speedometers stop working or break (8:23/17:58).
Geokinesis
Deoxys can control earth in various ways through psychic powers.
This is how it controls the meteors it’s commonly known for trying to crash into Earth.
Can also:
Invisibility
Deoxys is capable of turning invisible to avoid detection or ambush others for long periods of time.
Also used for sneaky escapes.
This was first stated to be due to it moving so fast, but it’s shown to stay invisible even while staying still.
Clairvoyance
Deoxys, through psychic powers, is able to detect the locations of others from across regions when holding onto something they own.
Can even locate multiple living things at once without the need of touching an object.
Energy Projection
Deoxys possesses the ability to launch energy-based projectile attacks with superb aim.
Can also shoot lasers from the crystalline brain on its chest.
Can utilize psychic energy to:
Delta Shield
Also known as Black Delta, this is a defensive technique formed when Deoxys uses both Reflect and Light Screen simultaneously.
Especially useful for regenerating its crystal brain should it be damaged.
In the Pokémon Adventures manga, this is the equivalent to the crystalline structure it hides in in the mainline games.
IQ Skills
IQ is essentially how smart one is. For Pokémon such as Deoxys, IQ can also grant passive skills depending on how high it is. These don’t always have to be on, meaning if one skill in particular wouldn’t be good to have in a certain situation, it is able to be turned off. The following is a list of all the IQ skills Deoxys has:
Item Catcher: Lets Deoxys catch and hold an item thrown at it, though it can’t do this if it’s already holding one.
Course Checker: Lets Deoxys automatically know if there are obstacles in the way before it performs an action.
Dedicated Traveler: Makes Deoxys focus more on traveling than fighting.
Item Master: Lets Deoxys use or throw its held items.
Exclusive Move-User: Makes Deoxys only use moves, though it won’t attempt to use them if it is out of energy to use a certain move or if using linked moves would delink them if used again.
PP Checker: Makes Deoxys not attempt to use moves if it is out of energy to use a certain move or if using linked moves would delink them if used again.
Efficiency Expert: Makes Deoxys target the opponent with the lowest HP if fighting against a group.
Status Checker: Makes Deoxys not use moves that cause status effects if the opponent already is inflicted with that status effect.
Nontraitor: Makes Deoxys unable to hurt its allies, even when forced to do so.
Self-Curer: Makes Deoxys recover from status effects faster than usual.
Quick Dodger: Makes Deoxys better at avoiding attacks.
Type-Advantage Master: Gives Deoxys a higher chance of landing a critical hit when attacking opponents with a type disadvantage.
Weak-Type Picker: Makes Deoxystarget the opponent with a type disadvantage if fighting against a group.
Trap Avoider: Makes Deoxys not step on visible traps on the ground.
Nonsleeper: Prevents Deoxys from being forced asleep.
Exp. Go-Getter: Makes Deoxys target the opponent worth the most experience points if fighting against a group.
Energy Saver: Makes Deoxys’s belly empty more slowly.
Lava Evader: Makes Deoxys avoid walking on lava.
All-Terrain Hiker: Lets Deoxys be able to walk on water, lava, and clouds.
Sure-Hit Attacker: Makes Deoxys’s regular attacks never miss their target.
Trap Seer: Lets Deoxys not set off traps when stepped on, which also makes them visible if they were hidden.
House Avoider: Lets Deoxys sense an ambush when one is about to happen.
Super Mobile: Lets Deoxys be able to walk on water, lava, and clouds, as well as be able to dig through walls when it walks into them.
Escapist: Lets Deoxys help others escape from dangerous situations.
PP Saver: Occasionally saves the PP of Deoxys’s moves, being specifically an 8% chance.
Gap Prober: Lets Deoxys throw items and use their moves through its allies so that they only hit opponents. Course Checker must be turned off for this to work properly.
Wary Fighter: Makes Deoxys step back a bit away from opponents if they miss an attack against one.
Sharpshooter: Raises Deoxys’s critical hit rate by 15%.
Hit-and-Runner: Gives Deoxys a 33% chance of evading counterattacks after it attacks an opponent.
Multitalent: Raises the maximum PP of all of Deoxys’s moves by 5 via sheer talent.
Exp. Elite: Makes Deoxys earn 10% more experience when defeating opponents.
Trap Buster: Gives Deoxys a 33% chance of destroying a trap it steps on instead of activating, though this also affects terrains that would benefit it.
Stair Sensor: Lets Deoxys use its intuition to locate the direction of the next stairs on the floor of a dungeon.
Wary Walk
A rare quality of Deoxys that passively lets it and any allies break and disable traps they step on, meaning they’re essentially immune to said traps.
Agitation
A state of agitation Deoxys enters when trying to be put under control emotionally.
It becomes harder to be controlled and moves and attacks much more mercilessly and wildly.
Will go out of this state if it takes too much damage or is continuously still trying to be controlled.
Shapeshifting
Deoxys has the ability to morph its entire body.
In its Normal Forme, it can transform its arms into either:
Tentacles for wrapping, slicing, strangling, or impaling attacks.
Humanoid arms for moves that require fists, blocking attacks, or simple tasks such as holding on to things (16:32).
Can even turn one arm into a tentacle and the other into a normal arm simultaneously.
Is also able to extend its tentacles to attack physically from a far distance.
Having four tentacles also helps in fighting off multiple opponents.
When dormant, it usually shifts into a triangular stone-like object that can fly around on its own.
Most importantly, it has the ability to change Formes to adapt to almost any situation.
Has a total of three other Formes that it can shift into.
Deoxys in the video games and manga require either being in specific climates or regions or meteorites to change Formes, but several Deoxys in other media have been shown to be able to change their Forme without the need of these requirements (1:07:37/1:19:15).
Can change it in a flash depending on the situation or to fake out its opponent into guessing which one it will go into.
Should be mentioned that its non-Normal Formes are immune to being emotionally controlled.
Its many Formes can also be emotionally controlled all at once if there are multiple sources of said control.
Formes
Normal Forme
HP: 50
Attack: 150
Defense: 50
Sp. Atk: 150
Sp. Def: 50
Speed: 150
Normal Forme is the most all-around of Deoxys’s Formes and is its, well, normal form it’s commonly seen using. Despite being the most all-around Forme, it has incredibly high Attack, Special Attack, and Speed, but at the cost of low HP, Defense, and Special Defense. This is still Deoxys’s safest Forme when it comes to having balanced stats, though can be seen as a lesser Attack Forme. That said, Normal Forme is the only Forme that’s been shown capable of turning its tentacles into hands.
Attack Forme
HP: 50
Attack: 180
Defense: 20
Sp. Atk: 180
Sp. Def: 20
Speed: 150
Attack Forme is the strongest of Deoxys’s Formes. It has sky-high Attack and Special Attack and has the same high Speed as Normal Forme. This Forme is about going all out with aggressive offensives (1:19:23), but it can’t last long with its appalling Defense and Special Defense. Deoxys will usually go into this Forme to perform strong attacks before changing back due to these low defenses. Via level up, it learns a lot of moves oriented around Attack and Special Attack such as Superpower and Zap Cannon, though its other Formes can use these moves as well.
Defense Forme
HP: 50
Attack: 70
Defense: 160
Sp. Atk: 70
Sp. Def: 160
Speed: 90
Defense Forme is the toughest of Deoxys’s Formes. With amazing Defense and Special Defense, it can tank many attacks via absorbing attacks by altering its cellular structure. It has decent Speed despite being a tank, but its downside is its very low HP, which it shares with all its Formes, not complimenting its super high Defense and Special Defense. Its Attack and Special Attack aren’t so great either. Deoxys will usually go into this Forme to defend against attacks it sees coming (19:08), stall for time so it can buff or heal itself, or use other setup moves. Via level up, it learns a lot of moves oriented around Defense and Special Defense such as Iron Defense and Amnesia, though its other Formes can use these moves as well.
Speed Forme
HP: 50
Attack: 95
Defense: 90
Sp. Atk: 95
Sp. Def: 90
Speed: 180
Speed Forme is the fastest of Deoxys’s Formes. Despite it having incredible Speed, it also has moderate Attack, Defense, Special Attack, and Special Defense. However, due to its low HP, it can’t make use of that decent Defense and Special Defense. Deoxys will usually go into this Forme to either get to other areas more quickly (19:06), dodge attacks (13:49 and 14:20), or blitz the opponent before they can even think (14:35), as well as other moves that allow it to buff itself or set up on opponents quickly. This also includes hit-and-run tactics and putting itself in better positions in combat. Via level up, it learns a lot of moves oriented around Speed such as Extreme Speed and Agility, though its other Formes can use these moves as well.
Feats
Strength & Attack Potency
Hurled dozens of rocks from the Grand Meteor Delta as an attack
Caused a meteor to fall towards the Alola region in its clash with Rayquaza (10:10)
Helped halt the Tree of Life’s ascent into the sun (239.0056 Zettatons - Planet Level)
Controlled the Grand Meteor Delta towards Earth, which would have destroyed it (896.61 Zettatons - Planet Level)
Speed
Dodged Rayquaza’s Hyper Beams (8:32)
Dodged lightning (11:10)
Flew itself and its meteor across the galaxy to Earth in the span of 10 days (986,174.91c - Massively Faster Than Light+)
Durability
Shook off being slammed into the ground by Rayquaza hard enough to create a crater (1:18:20/1:19:08)
Its brain survived a point-blank Hyper Beam from Rayquaza (11:24) and a crash landing into a mountain (11:33)
Survived Mega Rayquaza’s Dragon Ascent in Defense Forme, which destroyed the meteor Deoxys was in that would have destroyed the world
Destiny Deoxys’s meteor crash caused a massive crater in the North Pole (6:21/7:08/54:08)
Survived the destruction of the meteor it inhabited in many different continuities, all of which would have destroyed the entire world
Scaling
Rayquaza - Deoxys and Rayquaza are basically frenemies who have fought each other in countless continuities, some of them even when Rayquaza is Mega Evolved.
Obliterated the meteor Deoxys was in that would’ve destroyed the world in two continuities
Can reach escape velocity, and do so to reach space within seconds (1:33:17)
Mewtwo - This will only take into consideration the Pokémon Adventures manga, since that is the only time these two have fought with each other. That said, they definitely are comparable here, as Deoxys has overpowered Mewtwo.
Training & Experience
Locked down LaRousse City and kidnapped many of its citizens (48:24/48:56/52:46/1:00/15)
Helped stop Team Rocket’s battle airship from crashing into Vermillion City by locating 10 hidden Forretress commanded to use Explosion
Defeated Rayquaza (1:19:32/1:24:09) and Mewtwo before Red intervened
Weaknesses
While powerful and varied with its many Formes, Deoxys, as a Psychic-type Pokémon, is weak to certain move types, being Bug, Ghost, and Dark-type attacks. Also, each Forme does have their own downsides that an opponent can take advantage of if Deoxys is caught off guard, with Normal being frail but not having the highest attacking stats, Attack being super frail, Defense not being able to deal much direct damage, and Speed only possessing average offensive and defensive stats when another Forme in comparison has much higher of those same stats. As for Deoxys’s sight, strong electrical fields from too much machinery or living beings can make its vision blurry in the area of the interference (9:47/36:34/48:20/1:04:10), causing it to have more difficulties in battle, though it can destroy technology to help with this (36:48/45:43).
As for everything else, while Deoxys’s regenerating abilities are superb, if its whole body and brain are destroyed, it’s done for. Its brain is also a weak spot that can leave it completely stunned. It should also be noted that suffering enough damage will make it harder to change Formes, especially with attacks aimed at its crystal brain. That or it’ll change Formes at random. And while its regeneration is able to help it heal from missing body parts, those that obliterate its body take much longer (11:24/15:00/54:46 and 11:33), even years, sometimes indefinite, without outside assistance (3:03/1:15:05/1:16:16) or nearby meteors to absorb energy from (14:29/17:08). This will leave Deoxys’s crystal brain vulnerable. Also, while its non-Normal Formes help prevent emotional control, this can be circumvented by wearing it down or there are multiple sources of the control for its Formes. The same is said for when agitated since continuous attacks or emotional control will bring it out of it.
For its other powers, anything that is hermetically sealed will be immune to Deoxys’s auroras if they suffer from the geomagnetic waves they produce (4:28), and when disguising its Forme with an aurora, it can be seen through at specific angles to reveal its true Forme. Also, it has been shown that items or powers that allow one to see invisible things do have an effect on Deoxys when it's trying to be sneaky like that. Next, its Delta Shield does wear down if attacked repeatedly from multiple angles. Finally, Deoxys is hurt by disturbances in the geomagnetic waves (9:11/10:44/11:50), and can even force it to rapidly change Formes at random (16:04). This also affects its personal dimension (16:37).
Summary
Advantages
Has access to many different Formes that it can change on the fly to adapt to its opponent or use them to fake them out on which one it’ll go into
Has insane regenerating capabilities, both for its body and its core when using Recover, making it very hard to put down for good
Moveset grants it access to multiple psychic moves, elemental attacks, buffing and debuffing tactics, and health restoration
Can force opponents to exert much more energy with a combination of its Revive Robe and Pressure Ability
Flight allows for much better maneuverability
Auroras and invisibility allow it to deceive opponents in various ways
Its sight lets it see through objects, and can potentially even work on invisible opponents since it’s based on electric fields
Anything that’s mechanical has the risk of malfunctioning or being controlled through magnetism
Can have a numbers advantage with its duplication, with the Mystery Dungeon variation making it almost impossible to tell which is the real one
Mind control lets it make opponents its plaything
Can force battles to take place where it wants with its portal and dimension creation, possibly even letting it remove opponents from battle permanently
Is able to find hidden opponents through clairvoyance
IQ Skills and Wary Walk prevent traps from working and other various effects
Its non-Normal Formes and Agitation help prevent emotional control
Can form shields through moves, geokinesis, or its Delta Shield, with its Protect forcefield even being able to expand across an entire city and prevent others from escaping
Disadvantages
Weak to Bug, Ghost, and Dark-type attacks
Each Forme has their own downsides that an opponent can take advantage of if it can’t go into another Forme quick enough
Its electromagnetic sight suffers when trying to comprehend multiple machines or living beings all grouped together
If its body and brain are both destroyed, it’s done for, with its brain also being a general weak spot that stuns it or gives it trouble with its Formes when hit
Being weakened in general makes it struggle with going into its Formes
Can’t regenerate its entire body right away if its destroyed by a strong attack, leaving its crystal brain vulnerable unless there are some meteors nearby
Its emotional control resistance and agitation can be overcome via wearing it down or multiple sources of the control
Anything hermetically sealed won’t be affected by its auroras geomagnetic waves
At certain angles, disguising its Forme with an aurora won’t work
Powers that grant one the ability to see invisible opponents will definitely work on it
Its Delta Shield can be worn down by attacking it at multiple angles back-to-back
Disturbances in the geomagnetic waves will hurt it and give it trouble with using its Formes and making sure its personal dimension doesn’t go out of control
Speed Forme got shafted in its own movie
