It's not too hard to tame one of these if you have a deep sea taming pen/raft (it's possible! I'm surprised too). Just be wary of that bite it packs a punch. Lured it in the cage with some barys bred for speed and had a tribemate seal it in. Be prepared to wait a while and bring plenty of quetzal kibble or mutton if you can.
Center tip: as they have added the mosa to the center I've found the easiest way to knock one out is find one close to the bubbles get its Agro and swim in the bubble the mosa will get stuck and it can't hit you. Also this gives you unlimited oxygen and sanctuary from being attacked by anything else. ðŸ¤˜ðŸ¼