Core Mechanic: Enemies split into smaller versions when killed. You MUST use AoE towers to handle the chain reactions!
Enemy Split Types:
Towers: Splash (AoE, cheap), Bomb (large AoE, slow), Chain (hits 3), Poison (DoT kills whole family), Fire (burns)
Tips: Poison towers kill entire split families if the parent dies poisoned. Choke points with Splash + Bomb are essential.