Mutatrich

You must hit the Mutarich one hundred times to cause it to explode. It is invulnerable. Each time you hit it it gets bigger and does more damage.

The hit counter, invisible, does not count all hits per turn. So for example, if you hit it 20 time in one turn with a sadida with a forest, it will not go up by twenty. Even with a group of four hitting it 4 times per person will run afoul of the counter increase cap per turn.

I do not know what the counter increase cap per turn is though.