A fossil is an item that can be found in certain caves and dug up in the Underground. Fossils can then be resurrected into the Pokémon it is a fossil of. Each Generation has its own set of fossils consisting of at least two stage-two evolutionary families with Generation II being the exception.

Name	Image	Pokémon	Evolution	Generation
Helix Fossil		Omanyte	Omastar	I
Dome Fossil		Kabuto	Kabutops	I
Old Amber		Aerodactyl	None	I
Root Fossil		Lileep	Cradily	III
Claw Fossil		Anorith	Armaldo	III
Skull Fossil		Cranidos	Rampardos	IV
Armor Fossil		Shieldon	Bastiodon	IV
Cover Fossil		Tirtouga	Carracosta	V
Plume Fossil		Archen	Archeops	V

Resurrecting

In order to resurrect the fossil into a Pokémon, you'll need to visit a building, usually a museum.

• In Pokémon Red, Blue, Yellow, FireRed and LeafGreen, visit the Pokémon Lab on Cinnabar Island and enter the room on the far right.
• In Pokémon Ruby, Sapphire, and Emerald, visit the Devon Corporation in Rustboro City and have it resurrected by the scientist.
• In Pokémon Diamond, Pearl, and Platinum, visit the Oreburgh Museum in Oreburgh City.
• In Pokémon HeartGold and SoulSilver, visit the Pewter Museum in Pewter City.
• In Pokémon Black and White, visit the Nacrene Museum in Nacrene City.

Trivia

• Generation I is the only Generation to have more than two fossils, Old Amber.
• Generation II is the only Generation without fossils.