Sorry if such bug\issue have already mentioned
So it`s description
-You can gain experience by killing your`s heroes especially your female wizard by casting area-effect spells like Flare and Fireball, I killed her and then she auto-ressurected about 20 TIMES (250 exp after each killing)!!(Uhahaha!!)And thus I could gain to 3rd level after that she won`t ressurecting at all +)) So that`s it
Addition- I have tested wizard male and wizard female together
Male was killing yourself by fireballs and he died 5-6 times
Female killing herself by Flare she died about 20 times until leveled up to 3rd level
P.S I know it`s maniac and too severe from me but it`s just testing

Try yourself you`ll like it))