What would your special unit be able to do?

[John3:16]

I think a mobile spawn unit would actually be pretty overpowered, especially if you could spawn unlimited units for +1 wit and it is invincible when grounded. (oh wait, maybe you didn't mean could spawn unlimited number of units in a single turn)

Many maps are balanced because of the placement of the spawns. Being able to spawn snipers for instance right next to a base (even for +1 wit), would mean getting anywhere near a base is a win.