New Mechanic for Upgrading Hero

This is New Building : Hero Altar, we can upgrade hero here or just swap our hero to the other hero to deploy.

Going to WAR? but your hero still upgrading? Dont worry you can swap your hero to other hero while hero is upgrading, you can summon new hero (Skeleton King, The monk, or the other new hero).

Its same as Pet House mechanism, you can swap your pet, but in this time is hero. you can summon new hero with upgrading hero altar.

Preview image Inside Hero Altar

Preview image while Hero is upgrading

Preview image while upgrading inside hero altar