Evolving a Common or Rare Monster into its Epic form is more costly and unpredictable. Epic evolutions are only available using the Enhanced Crucible. You must raise the Heat Level to the highest possible level. If the evolution attempt is unsuccessful, residual Heat will be reset and one Flag will furl. However, an unsuccessful Epic evolution has a chance to produce a Rare instead. Generally, it is easier to evolve a Rare than a Common into an Epic.