You'll be sacrificing them to unlock the full potential of your chosen Vein of Evil throughout the game, but they can also help top up the treasury, or reinforce some walls.
Wither, Avarice and Fortify are the general all-purpose functions of the Sanctuary depending on your path through the Vein of Evil. They'll also unlock the 'super units'.
Wrath gives you access to Wither which saps away all the mana pools of your foes and stops them from recovering any for a period of time. Greed offers Avarice which exchanges your own mana reserves for a shower of gold coins in the Treasury. Lastly there's Fortify for Sloth, which can repair and claim walls adjacent to claimed land.
"With these new tools, and your own inimitably evil genius, you’ll have more ways than ever to melt your enemies down to their bones - or prevent the aforementioned from happening to the creatures who willingly fall under your own banner." Subterranean Games are also requesting feedback on the game's UI for which they hope to make a 'final revision'.
Check out the latest War for the Overworld update for more.
