Bats would be like barbarians that fly (stats wise). They would take up 1 space each, so you could overwhelm enemy defenses. And for a new twist, they would be flying but attack at melee range. They would still be untargetable by mortars and such, but they attack with bites, so they would use melee range.
Stats:
LVL 1, Size: 1 DE cost: 3-4 health: maybe 100? DPS: 12 Move Speed: 24
(stats are just a guess for right now, as I can't load the game to compare stats with barbs and archers)

