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Gastrodon front sprite from Pokémon Monomyth

No. 161 Returning · National Dex No. 423

Gastrodon

Sea Slug Pokémon

WaterGround

Damage calc →

Height
0.9 m (2′11″)
Weight
29.9 kg (65.9 lb)
Gender
50% male · 50% female
Catch rate
75 of 255
Growth rate
Medium Slow
Egg groups
Water 1 Amorphous
Egg cycles
20
Base friendship
70
EV yield
2 HP

Abilities

Gastrodon typically digests its food through absorption. Many smaller Pokémon land on Gastrodon and simply get sucked away.

Base stats

HP111
Attack83
Defense68
Sp. Atk92
Sp. Def82
Speed39
Total475

The species’ own values, before level, training or nature. Bars end at 200.

Changed in Monomyth

Same types and base stats as in the main games (National Dex No. 423).

Evolution

  1. Shellos front sprite from Pokémon MonomythNo. 160ShellosWater
    1. Level 30
      Gastrodon front sprite from Pokémon MonomythNo. 161GastrodonWaterGround

Where to find it

WhereHowLevelsChance
Battle Frontier form 2 formSuper RodLv 50–6040%
Camp TarragonSurfingLv 45–505%
Cascade CitySuper RodLv 45–5544%
Cascade CitySurfingLv 37–401%
Chamomile TownGrassLv 62–6620%
Elysium Base form 2 formSuper RodLv 50–6040%
Flooded CaveSuper RodLv 50–804%
His TrailSuper RodLv 50–6040%
Mandrake City form 2 formSuper RodLv 3555%
Mt. ThunderSuper RodLv 60–63up to 20%
Mt. ThunderSurfingLv 57–6130%
Oasis Cave form 2 formSuper RodLv 35–4016%
Old Bay CavesSuper RodLv 50–8019%
Old Bay CavesSurfingLv 50–705%
Old Bay Coast form 2 formSuper RodLv 50–6040%
Old Bay IslandSuper RodLv 50–6040%
Old Bay Island form 2 formSuper RodLv 50–60up to 55%
Old Bay Island form 2 formSurfingLv 50–80up to 4%
Overgrown Oasis form 2 formSuper RodLv 35–4016%
Port Ginseng form 2 formSuper RodLv 50–6040%
Port Ginseng Docks form 2 formSuper RodLv 50–6040%
Quiet ValleySuper RodLv 47–5740%
Quiet ValleySurfingLv 47–5210%
Reservoir Tunnel form 2 formSuper RodLv 35–4016%
Route 15Super RodLv 45–5020%
Route 30 form 2 formSuper RodLv 50–6040%
Solace Point form 2 formSuper RodLv 50–6040%
Tranquil CreekSuper RodLv 45–5020%
Victory RuinGrassLv 52–56, Lv 62–6920%

Moves

43 in all

Level up 17

LvMoveCategoryPowAccPP
1Harden, Normal-typeThe user stiffens all the muscles in its body to boost its Defense stat.Status——30
1Mud Sport, Ground-typeThe user kicks up mud on the field, reducing all Electric-type damage by 70% for 5 turns.Status——15
1Mud-Slap, Ground-typeThe user hurls mud in the target’s face to inflict damage and lower its Accuracy.Special20100%10
1Water Gun, Water-typeThe target is blasted with a forceful shot of water.Special40100%25
4Mud Sport, Ground-typeThe user kicks up mud on the field, reducing all Electric-type damage by 70% for 5 turns.Status——15
8Harden, Normal-typeThe user stiffens all the muscles in its body to boost its Defense stat.Status——30
12Water Pulse, Water-typeThe user launches pulses of water at the target. It has a 20% chance of confusing.Special60100%20
15Mud Bomb, Ground-typeThe user fires a hard-packed mud ball at the target. Has a 30% chance to lower Accuracy.Special6585%10
19Hidden Power, Normal-typeA unique attack that varies in type depending on the Pokémon using it.Special60100%15
23Ancient Power, Rock-typeThe user attacks with a prehistoric power. It has a 10% chance of boosting all its stats.Special60100%5
26Body Slam, Normal-typeThe user drops onto the target with its full body weight. Has a 30% chance to paralyze.Physical85100%15
30Recover, Normal-typeRestoring its own cells, the user restores its own HP by 50% of its maximum HP.Status——5
35Muddy Water, Water-typeThe user floods opposing Pokémon with muddy water. Has a 10% chance to lower Accuracy.Special9085%10
45Earth Power, Ground-typeThe user wildly erupts the ground under the target. Has a 10% chance to lower Sp. Def.Special90100%10
52Rain Dance, Water-typeSummons rain for 5 turns, which boosts Water attacks by 50% & halves Fire attack damage.Status——5
60Memento, Dark-typeThe user faints, and then harshly lowers the target’s Atk and Sp. Atk stats.Status—100%10
78Fissure, Ground-typeThe user opens a fissure beneath the target. If it hits, the target faints instantly.Physical—30%5

TM and HM 26

TMMoveCategoryPowAccPP
TM03Watercolor, Water-typeShoots water imbued with its true colors. The effect depends on its first non-Water-type.Special70100%10
TM05Infestation, Bug-typeThe target is infested for 4-5 turns. It deals damage each turn and prevents escape.Special20100%20
TM07Hail, Ice-typeSummons a hailstorm that lasts 5 turns. Every turn, it damages all non-Ice-types.Status——10
TM08Endure, Normal-typeThe user endures any attack with at least 1 HP. It may fail if used in succession.Status——10
TM10Hidden Power, Normal-typeA unique attack that varies in type depending on the Pokémon using it.Special60100%15
TM13Aurora Beam, Ice-typeHits the target with a rainbow-colored beam with a 50% chance to lower its Attack stat.Special65100%20
TM17Protect, Normal-typeThe user protects itself from incoming moves. It may fail if used in succession.Status——10
TM18Rain Dance, Water-typeSummons rain for 5 turns, which boosts Water attacks by 50% & halves Fire attack damage.Status——5
TM19Counter, Fighting-typeThe user retaliates against the last physical attack this turn, dealing double its damage.Physical—100%20
TM21Swagger, Normal-typeThe user enrages and confuses the target, but also sharply boosts the target’s Attack.Status—85%15
TM25Purify, Poison-typeBy purifying the target of status conditions, the user restores its HP by 50% of its max HP.Status——20
TM26Bulldoze, Ground-typeThe user stomps down on the ground, damaging & lowering the Speed of everyone around it.Physical60100%20
TM27Return, Normal-typeA full-power attack that grows more powerful the more the user likes its Trainer.Physical—100%20
TM28Dig, Ground-typeThe user burrows, then attacks on the next turn. It can also be used to exit dungeons.Physical80100%10
TM32Curse, Ghost-typeA move that works differently for the Ghost-type than for all other types.Status——10
TM37Sandstorm, Rock-typeSummons a 5-turn sandstorm, damaging all Pokémon except Rock, Ground & Steel-types.Status——10
TM39Cragalanche, Rock-typeAttacks opposing Pokémon after most moves. Power doubles if hit by the target that turn.Physical60100%10
TM41Substitute, Normal-typeCreates a decoy using 25% of its HP, which absorbs attack damage and many status moves.Status——10
TM42Reflect Type, Normal-typeThe user reflects all of the target’s types, making the user’s types equal the target’s.Status——15
TM43Secret Power, Normal-typeAn attack whose added effects depend on the terrain. Can be used to make a Secret Base.Physical70100%20
TM44Rest, Psychic-typeThe user sleeps for 2 turns, fully restoring its HP and healing any status conditions.Status——5
HM03Surf, Water-typeA big wave crashes down on all opposing Pokémon. It can also be used to cross water.Special70100%15
HM04Strength, Normal-typeThe target is slugged with a punch thrown at maximum power. Can be used to push boulders.Physical80100%15
HM05Rock Smash, Fighting-typePunches the target with a 50% chance to lower Defense. Can be used to shatter rocks.Physical50100%15
HM06Waterfall, Water-typeA rapid-charging attack with a 20% chance to flinch. Can also be used to climb waterfalls.Physical70100%15
HM07Dive, Water-typeThe user dives underwater, attacking on the 2nd turn. Can be used to dive in deep waters.Physical80100%10

Forms

Forms have no page of their own. They are labelled by what sets them apart, not by a name the game doesn’t give.

All sprites

Gastrodon front sprite from Pokémon Monomyth
Front
Gastrodon back sprite from Pokémon Monomyth
Back
Gastrodon shiny front sprite from Pokémon Monomyth
Shiny front
Gastrodon shiny back sprite from Pokémon Monomyth
Shiny back
Gastrodon animated sprite from Pokémon Monomyth
Animation

The game’s own animation.

Details
  • Steps5
  • Length75 ticks of 1/60 second
  • Step 1Frame 1 for 15 ticks
  • Step 2Frame 2 for 15 ticks
  • Step 3Frame 1 for 15 ticks
  • Step 4Frame 2 for 15 ticks
  • Step 5Frame 1 for 15 ticks

Every frame 2

Frame 1used 3×
Frame 2used 2×

Coat Lab

Gastrodon front sprite from Pokémon Monomyth, shown in its usual colours

2,754 possible coats

Usual colours, as in the Pokédex.

Quick guide 3 steps
  1. Pick a coat for each colour group, with its odds. Strength slides the shift from 1 to 8.
  2. Roll rolls a Pokémon’s coat the way the game does, from a random personality value.
  3. Share the link holds the coat you made.
Colour group 1
Colour group 2
Colour group 3

The in-game “Color Variants” option turns coats off. A shiny never gets a coat.

Pokémon Monomyth is a free fan game by Team Monomyth (monomyth.jp): Pokémon design, spritework, monster sounds and battle design are theirs. DexDB is an unofficial fan site, not affiliated with the team, Nintendo, Game Freak, Creatures or The Pokémon Company, and hosts no game files.