I got mine by going up on a cliff and it's really easy. so today I decided go to tame a spino with my argy, when I saw one I shot him a tranq dart then immediately hopped on my argy and flew up, after many shots it finally started running and I immediately started chasing him and after a while I finally got him down. then I started making a bed so I could save some time, I gave him the fish meat and a soothing balm, then I went to sleep and after coming out I saw this beast standing right next to my argy, at first I thought he just woke up but no... I actually tamed him