A number of older cards, such as "Fossil Dyna Pachycephalo" and "Fossil Tusker", include "Fossil" in their English names but are not part of this archetype, as their Japanese names do not contain
In the anime, the Rock monster must be banished from the player's Graveyard while the other monster must be banished from the opponent's Graveyard and have a specific type. In the Tag Force games, the Graveyard and Level requirements are the same as the anime, but they do not require the monster from the opponent's Graveyard to be a specific Type.
In the Japanese version, the "Fossil" Fusion Monsters each include the geologic era from which they originate in their names. In the anime and some video games, "Time Stream" supports "Fossil" Fusion Monsters based on the era in their name. The "Cenozoic" monsters are all Level 4 monsters that require a Level 4 or lower monster as material; the "Mesozoic" monsters are all Level 6 monsters that require Level 5 or 6 monsters as material; the "Paleozoic" monsters are all Level 8 monsters that require Level 7 or higher monsters as material.
|Dragon||Fossil Dragon Skullgar||N/A||none||N/A||Fossil Dragon Skullgios||Tyrannosaurus|
|Machine||Fossil Machine Skull Buggy||Dune buggy||Fossil Machine Skull Wagon||Station wagon||Fossil Machine Skull Convoy||Convoy|
|Warrior||Fossil Warrior Skull Bone||Pawn||Fossil Warrior Skull Knight||Knight||Fossil Warrior Skull King||King|
The Fusion Monsters all can only be Summoned by the effect of "Fossil Fusion", which banishes monsters in both Graveyards as Fusion Material. The Fusion Monsters all require a Rock monster and a monster of a particular Level to be used as material.