Alleygator

Alleygator is the first boss in Episode III. Deep Down Below, he is the guardian of the sewer gate and this artificial creature is based off of a sewer alligator.

Battle
The monster comes out of his tunnel and roars at the player, he activates bullets from his two guns at left/right then he moves into the tunnel before he roars and strikes to the other platform and moves back on his own, he shoots bullets from his mouth, activating his two guns again then moves to the tunnel again and roars to strike on the platform before moving on his own and repeat the pattern.

Trivia

 * He is the first reptile boss monster to be fought by the player.