the basic skeleton is honestly pretty damn overpowered
you might not realize why, but the math speaks for itself
1 skeleton = 3 coins spent, 1 coin gained
2 skeletons, merged at purchase = 6 coins spent, 3 coins gained
now you might look at that and think you spent 3 coins more than you earned, but since you can sell them for 2 coins..
the basic skeleton becomes a 2,2 for 1 coin essentially, highly valuable early game and good sell power mid-lategame
of course the same applies to the coin building, whatever it was called, although instead of a unit you get the promise of more coins, just a single round and the damn thing has already paid itself back and even made a profit