I have some tips for easy taming plesiosaur lvl 1-30. You need: Tamed Ichtiosaur, Oxygen balloon, Raw Prime Meat or Raw Meat, 60 narcotics or under, any crossbow, toxicant (or tranquilizer arrows, but this will be longer). That's all. You don't need traps or anything else. Just swim to plesiosaur's face on ichtiosaur, shoot toxicant (or tranquilizer) arrows, swim away from plesiosaur, reload, and repeat this again. After he go to sleep, just give him some meat, and feed narcotics sometimes. When you are on Ichtiosaur, anglers and mantas don't hurt you. This will be easy!

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