Bring a dolphin so it follows you, bring it to the top of ocean, mini game time use sickle an remove leachs in a timely fashion then feed it wait an do it again etc (Looks like it's a kibble tame exceptional or extraordinary it's like a bronto takes a while.

Level 100 saddle an has to be made in Tek rep

It’s 4x rate, and trying to tame a Shasta and had to use 15 extraordinary kibble to tame it. So the amount here on dododex is wrong info

It will be a passive tame, you go up to it with a pack of ichthyosaurs and scrape barnacles off its belly.

If you mess up the taming effectiveness, knock it out and wait for it to wake up again. Their torpor drains fast

It will be like the sea giga! 🦖

According to the dossier, now available on Discord, the method of taming is as follows. This hulking leviathan is a passive tame, however, to initiate the taming process you need a ‘school’ of Ichthyosaurs ( you’ll need a certain number of Ichtys to create the ‘school’), these will act as a distraction that enables you to do the next stage. Next, using a sickle, you swim to barnacle nodes on the Shastasaurus and harvest them. Assumably (since it doesn’t sate otherwise in the dossier) you have to repeat this several times.

Tame a dolphin, swim up to it and bring it to the water surface, that initiates a mini game with leeches that are on it, use a sickle and hit the leeches off, then swum to mouth and feed it extraordinary kibble, job done, just make sure there is no danger around, if it gets hit, taming % goes down to 0. Happy taming!

Lvl 90 took 14 extraordinary kibble on 3x event, official servers

Only tames with extraordinary kibble. Don't waste your time trying anything else. You'll swim away in shame.