Normal

Balanced unit with no special abilities.

Tank

Slow but durable. Built to absorb massive damage.

Runner

Fast and fragile. Can quickly slip through your defenses.

Healer

Restores health to nearby enemies, making entire groups much harder to kill.

Freezer

Reduces the attack speed of nearby towers with a chilling aura.

Elite

An empowered enemy with greatly increased health.

Boss

A massive foe with enormous health. The ultimate challenge of the level.