Just get a titanosaur with mods

Mmmm I would say dont tame it because

sigma

Make a trap of 4 stone battlements arrange the traps like a giga trap. after that, use your Quetzel and a canyon on its platform saddle to lure the Titanosaurus in close the final battlement then shoot it repeatedly in the head feed it lots of narcotics and crops wait a huge amount of time once tamed it will only last for one day