Thick Fat is an ability that halves damage taken from Ice and Fire-type moves. The ability was introduced in Generation III.

Pokémon

Pokédex	Pokémon	Sprite	Type	Obtained
#086	Seel			Natural
#087	Dewgong			Natural
#143	Snorlax			Natural
#183	Marill			Natural
#184	Azumarill			Natural
#220	Swinub			Dream World
#221	Piloswine			Dream World
#241	Miltank			Natural
#296	Makuhita			Natural
#297	Hariyama			Natural
#298	Azurill			Natural
#325	Spoink			Natural
#326	Grumpig			Natural
#363	Spheal			Natural
#364	Sealeo			Natural
#365	Walrein			Natural
#432	Purugly			Natural
#446	Munchlax			Natural
#473	Mamoswine			Dream World
#498	Tepig			Dream World
#499	Pignite			Dream World