I'd built a wood base on a cliff, Rexes, Carnos, and Allos, they all spawned there. I could trap the other two on rocks but these ones are just right to be annoying. I had too fight a pack off four with a dolphin, sniper rifle with 70 ammo, and a wild group of trikes. I found them while trying to tame a gali, I had to swim across the sea to herb Island. The gali tamed and died, then I teleported everyone else. It took ten minutes and all but six bullets but they all died.

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