Last Hero spell

[Vilk]

When you cast it on a troop, if this troop is fully killed the last unit of this troop survive with full health and last hero count decrease of 1.

For example 50 Snakes. Cast Last Hero on them. They are attacked and 30 are killed, Last Hero does nothing and there's now 20 Snakes. They are attacked again and all 20 Snakes are killed, the Last Hero make 1 Snake survive with full health.

Also at each round the Last Hero spell count decrease of one and this count also decrease of 1 each time the effect is used like quote above.

I haven't seen any good case to use this spell but in the giant turtle boss battle.