Here is the full list of all 25 Royal Heroes achievements.
Collect the whole set
Veni Vidi Vici!
Come to dark side. We have cookies. And extra spell slot.
Discover all earth spells
Find and kill all of famous vampires
Find and restore a famous weapon. Get Warping Power increase.
Warp a few times
Discover all water spells
Discover all air spells
Sacrifice a weak one to make your army stronger
You can't be a winner all the time
Do something useful. DOIT!
Hire a 4 star hero
Flawless victory - no casualties
Find and 'pet' at least 10 sheep
Discover all fire spells
Dont be a Batman - do it!
Discover all void spells
Clear a whole other dimension. Get Warping Power increase.
Craft a weapon that only the worthy can wield