Alpha Spitter

Life
It has 15/16 Lifepoints.

Behavior
Aggressive Creature. Attacks the player on sight with a big, exploding fireball that quickly splits into more, smaller fireballs.

Strategy
Get a rebar gun and quite a few healing items. Close combat is suicide. Try not to get hit with too many fireballs at once - they'll deplete an engineers life nearly completly within one volley. Try to find some cover (or build some beforehand or use the tractor) - shoot whenever possible and duck behind cover to heal.

Loot
Drops an Alien Organs.