Guts

Guts is an ability that was introduced in Generation Three that ''raises attack while affected by Burn, Paralsis or Poison Status Ailments.

Thirteen Pokémon have this ability.

Single Ability
246 Larvitar

276 Taillow

277 Swellow

Dual Ability
19 Rattata Run Away

20 Raticate Run Away

66 Machop No Guard

67 Machoke No Guard

68 Machamp No Guard

214 Heracross Swarm

217 Ursaring Quick Feet

236 Tyrogue Steadfast

296 Makuhita Thick Fat

297 Hariyama Thick Fat