[llamabeast]

Aaahh. Good point. I had forgotten that.

In that case I think perhaps we are stumped for non-commanders. Aquatic #firstshape won't work because they'll die anyway after one turn, and #onebattlespell won't work because it doesn't work for non-commanders. Are there any other options I've forgotten?

So I guess the only option is the 1hp thing (i.e. their first form only has 1hp, and their second form disappears after battle). You could say they agree to fight until their blood is first drawn, and then they will leave.