The fourth creature in the progression to Evolved (Feathered) Darkstar. You will need Raw Prime Meat to grow EvoFuel and also need the other items, listed below, to be able to evolve to the next stage. 1 EvoFuel takes 60 seconds to craft (.Ini configurable crafting speed) and it will autocraft EvoFuel as long as you have Raw Prime Meat in its inventory. When you have enough of each ingredient, craft the recipe and your creature will evolve to the next link in the chain, it's best to do that away from other creatures and remove anything else from the inventory including saddles. Tip! If your creature isn't producing EvoFuel then try picking it up with a "Soul Trap" from the Dino Storage v2 Mod or a Cryopod then releasing it to see if that re-starts crafting.