Here is the full list of all 15 Epic Eon achievements.
Win 15 total matches as Humans
Win 15 total matches as Undead
Win 15 total matches as Barbarians
Win 15 total matches as Elves
Win 15 total matches as Orcs
Win 15 total matches as Dwarfs
Win 15 total matches as Aliens
Unlock all campaign missions
Win 100 total matches as Humans
Win 100 total matches as Undead
Win 100 total matches as Barbarians
Win 300 total matches as Elves
Win 100 total matches as Orcs
Win 100 total matches as Dwarfs
Win 100 total matches as Aliens