I was just flying around mam the island and then i find him on peaceful island i attacked him with my pteranodon with 1000 hp an he just only one attacked me and... Pteranodon-350hp i was like I WANT THAT TITAN!!!
Super easy to kill with a Lightning Wyvern as stated before. My addition to the top would be try to bait it to the moat around red ob into the upper falls where the snow and sand meet on the Easter coast. Then they don't run as much.
I got level 95 very fast by killing Titanosaurs. The best way is to use a lightning Wyvern and fire it from above, watch your stamina. You can also use a very good Giga (good melee and good saddle is a must) to kill it fast, try to hide behind a Redwood tree, take your time and watch your stamina. If anything goes wrong (Giga stuck in a tree) dismount from it and shoot arrows at the Titan, it will start chasing you, hide behind a tree and wait. The titan will become passive. Good hunt and don't forget the broth for exp x2 ! :)