its really hard to kill. taming however is very hard. Make stone walls and make them five tall and more if you need to.then make its length and with large enough for the titanosaur to fit through then atack the titanosaur with an argy to make it follow you intothe pen. then get your frend to close up thecage behind the titanosaur. then once hes traped make a tower next to the cage out of reach from the titanosaur. then shoot the thing until its knoked out.
put your structure resistance to max. if your on a server use metal walls insted.
if your in mobile don't try to tame a titan near the ocean because the ai of the titan in ark mobile is dumb and can drown themselves so when you are taming a titan if it's near the ocean don't tame it it might have a chance to drown itself