Minor Race Iyana - city garrisoned with Elemental Lord.

In tactical battle, Morale for my army was reduced to 0. Got slaughtered.

In auto battle, morale didn't enter into it. Also, Elemental Lord didn't use special ability. Sovereign's Melting Touch spell did max damage on each cast. Also, Sovereign targeted weak, useless Miners first instead of dangerous Elemental Lord.

Solved dilemma by entering Tactical combat, freezing Elemental Lord, crushing puny other units, then hit auto battle - Sovereign instantly cast Melting Touch for max damage on Elemental Lord. Won battle, no damage.