How can Gliscor and other tanks be countered in competitive battling?

Question

While I was playing Pokemon showdown I got into a fight with a gliscor and well we all know the toxic healing roost gliscor tank so here's the battle https://play.pokemonshowdown.com/battle-gen7ou-842181305 how do I trap my opponent into taking out a tank

Comments

You can KO or force out Gliscor pretty easily if you use a special attacking Water or Ice type. Generally, Pokémon with extremely high attacking stats are good for dealing with tanks and walls.

252 SpA Choice Specs Greninja-Ash Water Shuriken (20 BP) (3 hits) vs. 244 HP / 76 SpD Gliscor: 384-456 (109 - 129.5%) -- guaranteed OHKO after Poison Heal

252+ Atk Choice Band Tapu Bulu Wood Hammer vs. 244 HP / 0 Def Gliscor in Grassy Terrain: 400-472 (113.6 - 134%) -- guaranteed OHKO

Answer 1

Ice-types and Ice Coverage: Strong Ice-types such as Kyurem-B and Weavile are able to outspeed and OHKO Gliscor. Similarly, Gliscor should be cautious of switching into Tapu Koko, Magearna, and Medicham, as they can all carry Ice-type coverage.
Offensive Water-types: Offensive Water-types such as Greninja, Keldeo, and Gyarados can all threaten Gliscor with their powerful STAB moves and potentially use it as setup fodder. Defensive Water-types such as Mantine and Rotom-W can attempt to PP stall Gliscor; however, they should be wary of getting their item removed or getting afflicted by Taunt.
Pokemon immune to Earthquake: Defensive Flying-types such as Celesteela and Zapdos are immune to Earthquake, but they do not appreciate their item being removed. Mega Latias and Mega Latios can both wall any set without Toxic and set up Calm Minds or OHKO Gliscor with Ice Beam. However, Flying-types that are suceptible to Toxic need to be wary of it when switching into Gliscor.
Grass-types: Grass-types such as Tangrowth, Tapu Bulu, and Ferrothorn are all able to switch into Gliscor and exploit its passivity. Tapu Bulu with a Z-Crystal can freely switch in, set up a Swords Dance, and recover any damage with the combination of Horn Leech and Grassy Terrain. However, Grass-types do have to be warry of being broken by offensive sets or crippled by Toxic in the case of Tangrowth and Tapu Bulu.

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