Fossil was the fourth major expansion released for the Pokémon Trading Card Game, arriving in 1999 when the hobby was experiencing explosive growth. The set drew inspiration from prehistoric themes, featuring fossil-themed cards and introducing new mechanics that expanded competitive play. First Edition printings from this era have remained particularly sought by collectors due to limited production runs compared to later unlimited versions. Omastar represents one of the set's evolution lines, showcasing the water-type fossil Pokémon line that appealed to collectors building complete sets. The card captures the paleontological theme central to Fossil's identity, making it memorable to those who opened packs during the TCG's golden age of the late 1990s.