Ketos/Cetus (plural Ketea/Cetea), the aquatic monster.
This large NPC swims around and attacks you if you get too close. If spawning one, make sure the body of water you're spawning it in is large enough for it to swim in.
Mod also comes with script that can be enabled to add Ketea to campaign levels, and showcases ways to use their potential, particularly on demolition levels.
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