Instead of trash force tame tips why don’t I give you some useful info that you can put into practice.
On official smalltribes I went in with 3 rexes one yuty and a deinonychus. I failed. I didn’t fall down the hole or anything, I simply didn’t have enough firepower.
Forget rexes, unless you want them to tank the boss. The Dino you need for bosses is the deinonychus. As fake as it sounds you can beat it on official with even ONE deinonychus. The reason it can destroy the boss and basically any other boss is because they are the only Dino in the game that does bleed damage to bosses. Bring multiple deinonychus, have some hiding away from the action as a backup because if you bring one and it dies then you lose. I am going to be fighting it again but this time with a pack of deinonychus and 2 stegos (mateboosted) to tank while I do the killing. Search it up on YouTube, Rex’s aren’t the way anymore it’s deinonychus, those feathery raptors, on valguero and fjordur. Also you can easily get artifacts you need for gamma in crystal isles, you legit just need 3 artifacts and you are in. Make sure your deinonychus is a very high level and give it very good health and Stam if you like. Good luck boys.