How do you kill a summoned phoenix?

I didn't know that a hero at this level gains such an ability. If so, then the summoned creature is no different from a non-summoned one; the Herald doesn't care, which means the abilities are the same as well.

Can you get the "Banish" ability? (If the hero is level 30, it will deal (30 + Summoning Magic level (max Expert - 3)) * 10 = 330 damage to summoned creatures, which is quite good, especially if there are other summoned creatures besides the Phoenix).