Don't laugh, I had a sea cucumber come right at me, chased me down, knocked my video camera right out of my hands, then ripped right through my mouthpiece hoses, then knocked me unconscious. No diver that has ever fought back has lived to tell. They're the most foul, cruel invertebrates you'd ever laid eyes on!
Some are vicious killers with mean streaks a mile wide! I've seen the bones of 50 divers strewn about their lairs! You've been warned!
