From Bulbapedia, the community-driven Pokémon encyclopedia.
The Cover Fossil (Japanese: ふたのカセキ Cover Fossil) and Plume Fossil (Japanese: はねのカセキ Plume Fossil) are Fossils which can be regenerated into Tirtouga and Archen, respectively.
In the games
In Pokémon Black and White, a Backpacker on the first floor of Relic Castle has found both of the Fossils, but claims they are too heavy and offers one of the Fossils to the player, and the player must choose one of the two Fossils. The Fossil that is not chosen is kept by the Backpacker, and cannot be obtained in-game.
If brought to the Nacrene Museum, the Cover and Plume Fossils can be regenerated into Tirtouga and Archen, respectively.
In Pokémon Black 2 and White 2, the former Gym Leader Lenora will give the player either fossil when they reach Nacrene City later on in the game after defeating the Elite Four. Just like before the player must choose one of the two fossils and then speak to Lenora to revive it.
The item description for the Cover Fossil states "A fossil of an ancient Pokémon that lived in the sea in ancient times" and the item description for the Plume Fossil states "A fossil of an ancient Pokémon that flew in the sky in ancient times. It appears to be part of its wing."
In the anime
A Plume Fossil in the anime
A Cover Fossil in the anime
A Plume Fossil appeared in Archeops In The Modern World!. Prior to the episode, Lenora gave a Plume Fossil to Professor Juniper and Fennel. They successfully resurrected a female Archen from the Fossil using Musharna's dream energy. With the help of Ash and his Tranquill, Archen learned how to fly and then evolved into Archeops.
A Cover Fossil appeared in A Restoration Confrontation! Part 1. It was found by Ferris and later stolen by Team Rocket, who, by using the stolen data from Juniper and Fennel's fossil resurrection machine and the stones stolen from the Chargestone Cave, managed to revive it into a Tirtouga. It evolved into a Carracosta in the next episode, and was eventually returned back to its own time through a time gate in Twist Mountain.
In the TCG
The following is a list of cards named Cover Fossil or Plume Fossil.
- While the item description for the Plume Fossil states the Fossil came from a "Pokémon that flew in the sky", the backpacker who gives the Fossils mentions that the Plume Fossil is from a Pokémon that lived in an ancient forest, but could not fly.