I think the idea of a fossil in some sense is cool.
Howeve,r for a pretty hefty price, you don't get nearly the payback of antimatter. Then again your opponent can't counter antimatter if you play fossil. That is about the only factor that makes it worth the hefty price. I guess it could help with EM and maybe to get a butterfly effect played.
Anyhow I think it is a little weak. Maybe change the effect slightly or lower the cost by 1?