Gastrodon, the Sea Slug Pokémon. Its whole body is sticky with mucus. In the past, this form of Gastrodon was by far the more numerous one. It appears on beaches where the waters are shallow. Once it catches prey, it will slowly melt them with its mucus before slurping them up. They normally inhabit rocky seashores, but in times of continuous rain, they can sometimes be found in the mountains, far from the sea. Fishers say that they didn't see many of these Pokémon in the past, but this form of Gastrodon is now increasing in number.
Overview
Ever since Storm Drain’s buff in generation 5, Gastrodon has been a niche defensive option as the generations pass by and the ninth generation is little different. Water Ground is one of the best typings in the game with incredible Rock and Fire resistances along with an Electric immunity with only a single weakness to speak of. With Storm Drain, Gastrodon adds a Water Immunity to that, enabling Gastrodon to wall a wide range of Pokémon even before we get into the synergies between Storm Drain and Terastalization. Aiding in Gastrodon’s walling duties is its fantastic base 110 HP, making Gastrodon surprisingly durable, especially with access to natural recovery in Recover, allowing Gastrodon to take repeated attacks and remain steadfast against the assault. Add in Entry Hazard support, forced shuffling with Yawn, and pHazing with Clear Smog, and Gastrodon has all the tools to succeed as a defense Pokémon.
All tools except actual Defense. While 82 Special Defense is perfectly serviceable with such high HP, 68 Defense is a significant flaw that prevents Gastrodon from going the distance. The loss of Scald in the generation shift is sorely felt on this front, leaving Gastrodon with more ephemeral ways of addressing physical attackers in Chilling Water, Stockpile, and Acid Armor, none of which are ideal for a pivoting defensive set piece. What is even more dire is Gastrodon’s achilles heel in its typing, a quadruple Grass weakness that has it quaking at the very hint of a leaf. It is an easily exploitable weakness too, given Gastrodon’s unsurprisingly slug slow speed, forcing it to take a hit before acting in any avenue, and worsening the value of its base defenses. Furthermore, merely decent offenses leave Gastrodon rather passive, relying on Storm Drain boosts or type advantages to carrying it through offensively. While Gastrodon’s shield is rather flawed, this has not stopped this slug from gumming up the offenses of many a foe.
Positives
Water Ground typing is a strong candidate for one of the best in the game, with many resistances and good offensive coverage only marred by one weakness.
Storm Drain is an incredible ability, granting Gastrodon an invaluable immunity and self-setup on Pokémon that otherwise struggles to do so.
Base 110 HP gives Gastrodon some good hit taking ability, which improves to actual longevity with access to reliable recovery in Recover.
Negatives
Base 68 Defense is rather poor, making Gastrodon far easier to take down on the physical side.
Base 39 Speed is horrid, forcing Gastrodon to rely on its defenses to compensate.
Quadruple weakness to Grass is an incredibly easy weakness to exploit and remove Gastrodon quickly.
Outclassed by better Psychic types.
Movesets
No Shell No Problem
-Stealth Rocks
-Recover
-Earth Power
-Sludge Bomb
Ability: Storm Drain
Item: Heavy-Duty Boots
EVs and Nature:
252 HP / 176 Def / 80 SDef
Calm Nature
Gastrodon slots well as part of a team’s defensive backbone. Gastrodon’s stifling of an opposing team’s Water and Electric based offense with its excellent immunities as well as good special bulk, makes a reliable pivot into such attackers time and time again. Gastrodon’s great base typing is fantastic at forcing switches and given its longevity makes it a great hazard setter, repeatedly establishing Stealth Rock to chip away at the opposing team. Recover is what gives Gastrodon its longevity, being able to recover from nasty blows and making it very resistant to being worn down, unlike its opposition. While Gastrodon isn’t expected to take big one hit knock outs, it still commonly runs STAB attacks and coverage to help grind opponents down. Earth Power is Gastrodon’s favored STAB move, threatening the Electric types Gastrodon is meant to handle while still being a solid neutral hit against opposing Water types. This is complimented by Sludge Bomb that ruins opposing Grass types that try to switch into it, with a nasty chance of poisoning that can punish neutral switch ins, while the Poison status immune Steel and Poison types want nothing to do with Gastrodon due to its STAB Earth Power.
Tera Types:
Gastrodon’s Water Ground typing is a large part in why it is used and often prefers to switch out over Terastalizing for an advantageous matchup. However, many Water type’s secondary STABs often mandate Gastrodon to Terastalize to completely shut such targets out. To say nothing of Terastalizing out of Gastrodon’s horrid quadruple Grass weakness. To better answer opposing Water types, Tera Fairy is a popular option, allowing Gastrodon to comfortably sit in front of Keldeo, Greninja, and Crawdaunt without much issue on top of being a solid type in general. Tera Poison is also a strong option, giving an all-important Grass resistance and Toxic Immunity, while still allowing Gastrodon to handle Keldeo, Azumarill and Toxapex. Bolstering Sludge Bomb to the point of STAB is a nice bonus as well.
EVs and Items:
As with most defensive Pokémon it is hard to go wrong with Max HP investment, though Gastrodon’s HP is certainly high enough to get away with not maximizing investment. Given EV spread spares just enough Special bulk to nearly avoid being 2HKO’d by Greninja’s Ice Beam, and Keldeo’s Focus Blast while still having enough physical bulk to almost always stomach two Excadrill’s Earthquakes, as well as merely being 3HKO’d by Rhyperior, Krookodile, Swampert and Metagross. Alternatively, one could go full Special Defense and HP for Gastrodon to act as a team’s special sponge, and greatly improve its matchup into Greninja and Keldeo as well as better handle Latios’ Draco Meteor, and survive Manaphy’s Energy Ball without Terastalizing. Heavy-Duty Boots is preferred, as Gastrodon is constantly switching into attacks and out, so being able to avoid being worn down by Spikes or ruined by Toxic Spikes is paramount. Leftovers is also a strong option, getting plenty of mileage from Gastrodon’s high HP and improving its staying power over protracted battles. Rocky Helmet is more niche but punishing for the many physical attackers looking to exploit Gastrodon’s low defense.
Partners:
:
Allies that can switch into Grass attacks are vital for Gastrodon as it needs an ally to cover its gaping weakness. Skarmory is an all-around excellent example, loving Gastrodon handling Water, Electric and Fire attacks for it, while it can safely absorb Grass attacks, alongside with their contrasting defenses make for a solid backbone. The fact that Skarmory can set whatever hazard Gastrodon lacks is just amazing. Mandabuzz also works well, especially if not running Heavy-Duty Boots for hazard control and crippling targets with Toxic. Skeledirge and Heatran are more traditional answers, forming a Water-Fire core and loving the anti-Water support Gastrodon provides.
Gastrodon also finds itself an anchor for Sand teams, being a Water Immune Pokémon that doesn’t take Sandstorm chip invaluable for what is otherwise a very difficult matchup for such teams. As a result, Hippowdon, Tyranitar and Excadrill all make for consistent partners, though one must take care not to exasperate a team’s Grass weakness.
Other Options:
Spikes is just as viable as Stealth Rocks for hazard setting and is up to personal preference.
Ice Beam offers incredible coverage into both Grass and Dragon types and can be a strong consideration over Sludge Bomb.
Clear Smog allows Gastrodon to prevent setup sweepers from using it as fodder and can stop a one time sweep in its tracks.
Doubles and VGC Options
Despite Gastrodon’s humble appearances, it has two world champ titles under its belt from the previous two generations. This is because Gastrodon’s unique combination of traits make it one of the best answers to Rain and Kyogre in the game. The passive Water immunity and redirection from Storm Drain is incredible, hampering every Water type out there, and Gastrodon’s Ground subtyping is especially apt against Rain in preventing it from being ruined by Kyogre’s Thunder or Archaludon’s Electro Shot. Add in a neutrality to Ice Beam and Gastrodon’s good special bulk and Kyogre struggles to KO Gastrodon in a timely manner. Even out of rain, being able to stop Commander Dondozo cold with Clear Smog and prevent it and Urshifu-Rapid from targeting Gastrodon’s teammates with their Water STABs is invaluable. Not to say anything of Gastrodon’s incredible support movepool, with Chilling Water, Yawn, Icy Wind and Helping Hand allowing Gastrodon to be a flexible support piece that can fulfill whatever one’s team needs. That has not stopped this generation from being one of the roughest for Gastrodon. As a Water Absorb Pokémon with active redirection with Follow Me, Wellspring Ogerpon fulfills many of the same roles as Gastrodon on top of actively threatening most Water types with its powerful Grass STAB, including Gastrodon, who is rather passive if it can't get a Storm Drain boost. The prominence of Grass types this generation causes further strife, with every team running at least one of Rillaboom, Ogerpon, Amoonguss, Whimsicott, and direct counters to Gastrodon.
Sea Slug Brain Drain
-Earth Power
-Yawn
-Recover
-Protect
Ability: Storm Drain
Item: Leftovers
Tera Type: Fire/Fairy
EVs and Nature:
116 HP / 252 Def / 140 SDef
Bold Nature
Gastrodon plies its trade as a team's sponge and answer to many Water typed attackers, taking advantage of its excellent blend of typing, ability and special bulk to completely shut such attackers out. Earth Power is a near constant on every Gastrodon, being neutral STAB against the Water types it is meant to answer, while still boasting valuable coverage into other Pokémon like Incineroar, Raging Bolt, Miraidon, Iron Hands, Zacian-Crowned and Zamazenta-Crowned. Yawn is premium disruption, forcing opponents to switch out or lose turns to Sleep, swinging momentum into Gastrodon's favor. Recover grants Gastrodon incredible longevity, allowing it to outlast non Specs Miraidon and Raging Bolt while preventing it from being worn down from neutral hits until it can't perform its duty any more. Protect rounds out the set as a Doubles staple, stalling out opposing field conditions, stalling for allied setup, keeping safe while Gastrodon's partner KO's the offending Grass type, etc.
EVs are to maximize physical bulk while still leaving enough special bulk to survive non Specs Miraidon's Draco Meteor and pushing Kyogre's Ice Beam to 4HKO range with Leftovers. As for Tera types, Tera Fire is a popular option, giving Gastrodon a valuable Grass resistance while Storm Drain renders the Water weakness moot, allowing Gastrodon to wall Grass-Water-Fire cores. Tera Fairy is also potent, allowing Gastrodon to outright wall Urshifu-Rapid and most Dondozo due to being immune to Water STAB in Storm Drain and rending Close Combat, Body Press and Order Up ineffective.
Preferred Partners & Options:
Pokémon that struggle against Water types love Gastrodon and its Water surpressing antics. Fire types in particular make for good partners with Gastrodon, threatening the Grass types that trouble it so. Ho-oh with its Sacred Fire doing a lot to compensate for Gastrodon's poor Defense while still boasting Flying STAB to threaten Grass types in Rain. Incineroar is also incredible providing invaluable physical damage mitigation with Intimidate, Will-O-Wisp and Parting Shot. Honorary Fire type Groudon can also make use of Gastrodon's anti Water services. Ting-Lu is another excellent partner, further increasing Gastrodon's already good special bulk, and can help win grind games between Ruination and Sand Tomb.
Gastrodon also finds itself a common partner to Miraidon surprisingly enough, running Electric Seed that goes miles in addressing Gastrodon's poor Defense. Such Gastrodon would do best in discarding Yawn for other support such as Icy Wind, Chilling Water and Helping Hand.
Ice Beam is great coverage into the many Dragon types running around and allows Gastrodon to flip the tables on Grass types if running Tera Fire.
Helping Hand bypasses Gastrodon's low speed and unimpressive offense pre-Storm Drain to make its teammate even more threatening.
Muddy Water is spread Water damage and can help grind opponents down.
Icy Wind provides decent speed control.
Countering Gastrodon
While Gastrodon has garnered fame as a hard stop to Water types as well as being a general good wall, these strengths are contrasted by easily exploitable weaknesses.
First and foremost is Gastrodon’s horrid weakness to Grass attacks. Nothing is faster in removing Gastrodon and ripping out a portion of a team’s backbone. Any STAB Grass attacker can do the job especially given Gastrodon’s slug slow speed. The problem is getting Gastrodon to stick around for the Grass attack. The best way to go about this are Water and Electric type lures with Tera Grass Tera Blast. Especially Electric types like Sandy Shocks, and Magnezone, this is not a tall ask given how Tera Grass synergizes with their base Electric to begin with.
Water attackers with strong secondary STABs can also threaten Gastrodon a great deal, especially when targeting its weaker Defense. Banded Crawdaunt OHKO’s max HP Gastrodon with Knock Off, as can Banded Azumarill with Play Rough while Specs Keldeo solidly 2HKOs with Secret Sword. Do note that Gastrodon often carries Teras to deal with these secondary STABs, so until Terastalization is expended, Gastrodon can still flip the matchup on its head. Life Orb Pelipper can also 2HKO Gastrodon with Hurricane, though this is contingent on Gastrodon not running a Special Defense boosting nature.
Otherwise, strong physical attackers can dispatch Gastrodon. Wide Lens Maushold can a strong chance to OHKO after 1 layer of Spikes, as does Choice Band Haxorus. Banded Slither Wing can also OHKO after 1 layer of Spikes but also boasts phenomenal Special Defense that makes it difficult for Gastrodon to threaten back. Guts Conkeldurr also has a small chance to OHKO after a layer of Spikes with Close Combat. Physical Ground attackers are a bit more tenuous given Gastrodon’s access to Water STAB and Ice Beam, but given Gastrodon largely revolves around checking Water types, it is not uncommon to see it without one if not both. Flygon abhors Ice Beam, but walls Sludge Bomb + Earth Power variants and can 2HKO with Banded Outrage. Banded Mamoswine dislikes Water STAB, but otherwise can also 2HKO with Earthquake.
Locations in Games
Red/Blue/Yellow:
Not in game
Gold/Silver/Crystal:
Not in game
Ruby/Sapphire/Emerald:
Not in game
FireRed/LeafGreen:
Not in game
Colosseum/XD:
Not in game
Diamond/Pearl/Platinum:
Routes 213, 218, 221, 222, 224 & 230, Fuego Ironworks (Diamond/Pearl)
Route 205 South, Route 212 South, Route 213, Pastoria City, Canalave City, Valley Windworks, Route 218, Route 224, Fuego Ironworks (Platinum)
HeartGold/SoulSilver:
Evolve Shellos
Black/White:
Trade from Black 2/White 2
Black 2/White 2:
Evolve Shellos
X/Y:
Friend Safari
Omega Ruby/Alpha Sapphire:
Evolve Shellos
Sun/Moon:
Ancient Poni Path, Exeggutor Island, Poni Wilds
Ultra Sun/Ultra Moon:
Ancient Poni Path, Exeggutor Island, Poni Breaker Coast, Poni Wilds
Let's Go, Pikachu!/Let's Go, Eevee!:
Not in game.
Sword/Shield:
Route 9, Dusty Bowl, Galar Mine No. 2, Giant's Mirror
Max Raid Battles: Bridge Field, Dusty Bowl, Giant's Cap, Giant's Mirror, Lake of Outrage, Rolling Fields, South Lake Miloch, West Lake Axewell
Brilliant Diamond/Shining Pearl:
Route 218, Route 221, Route 222, Route 224, Route 230, Fuego Ironworks, Grand Underground
Legends: Arceus:
Obsidian Fieldlands: Sandgem Flats, Ramanas Island or nearby
Cobalt Coastlands: Seagrass Haven or nearby
Obsidian Fieldlands: Massive Mass Outbreak
Cobalt Coastlands: Massive Mass Outbreak
Scarlet/Violet:
West Sea: Casseroya Lake
East Sea: North Province Area One
Fixed: North Province Area Three
Tera Raid Battles: 4 Star Raid Battles
Anime Appearences
