I use to go to the beach, swim out a little bit until it agro. Then swim to land again and the cnidarias are following me to land. When it I am standing on land it stops. Then I can easily kill it without taking any damage.
Really op and so easy to get from spawn. New players just wait till night, find the glowing blue things, and shoot them from shore. Super good for keeping creatures unconscious if they have a high topor drain. Also tastes absolutely great
For the people complaining about the iguanadon being one of the highest rating, its because of aberration. The iguanadon harvests a bunch from the red hallucinagenic mushrooms that are unique to aberration.