Forretress, the Bagworm Pokémon. Forretress is the evolved form of Pineco. Its entire body is covered in a steel hard shell.
– Ash’s Pokedex
Forretress is one of the two Bug/Steel types introduced in Gen II (the other being Scizor). Bug/Steel is a pretty good defensive typing, seeing how it only has one weakness (though 4x) to Fire.
Forretress is one of the Pokemon that don’t actually show its face. Only its eyes stare out fro under its fortress of a shell thing, so we don’t know what it looks like under there.
In the anime, Brock’s Pineco evolved into a Forretress. It’s called out usually to rapid spin stuff away.
Because of its good defensive typing, and good Defense stat and support moves, Forretress is pretty standard as a supporting physical wall. It can learn all of the entry hazard moves (Toxic Spikes, Spikes, and Stealth Rock), as well as the move that removes them (Rapid Spin). It’s neutral to Stealth Rock and immune to Toxic Spikes, making it a good set-up Pokemon. Aside from entry hazard setup/removal, it can learn other supporting moves like Light Screen and Reflect. Offensive-wise, it has Gyro Ball, which with its slow Speed and decent Attack, can pack a punch. It also learns the powerful Explosion.
Its ability Sturdy became more useful in Gen V, with Sturdy’s effect being changed for the better. Forretress’ Dreamworld ability is Overcoat, which is useful for stall walling in certain situations, since it would be immune to Hail damage (it’s already immune to Sandstorm due to its typing).