2 groups of brutes would die while trying unsuccessfully to kill a Smarty?
4 groups of Archers would die while trying unsuccessfully to kill a Smarty?
That make the Smarty tougher than I thought, or Archers a lot weaker than I thought.
Okay thanks, I updated the OP to clarify.
Yes, 2 groups of brutes would die unsuccessfully killing a Smarty.
Yes, 4 groups of archers would die unsuccessfully killing a Smarty.
Brutes spawn in squads of 4 units, archers in squads of 3. So that means 8 brutes will lose, or 12 archers will lose.
I have not yet done much with mixed groups. But now with this sandbox that is trivial. You can imagine half archers and half brutes, with the brutes taking most of the damage, might work out best.