Splat

The blobs crawl along the path. Place towers beside it, upgrade them and let none through. Each level has its own path and more waves.

Bolter – fast, cheap, weak against armor

Cannon – splash damage

Froster – slows everything in range

Tesla – lightning chains across several blobs

Scout – hits anywhere, targets the toughest

Venom – poison that eats through armor

Miner – lays mines on the path

Slicer – saw blade cuts through a whole line

Prism – beam heats up on a single target

Beacon – boosts nearby towers