Gliscor's main role is to be a physical wall/staller. It has great physical defense, passable HP, and Poison Heal which lets it restore 1/16 of it's HP every turn, which is twice the amount of Leftovers.
Set:
Gliscor @ Toxic Orb
Ability: Poison Heal
EVs: 244 HP / 40 Def / 224 Spe
Impish Nature
- Substitute
- Protect / Roost
- Toxic
- Earthquake