When you do drag and manticore you’ll need to be on a good saddle and bring in stimulants because when you try to trap the dragon (surrounding it in all sides) manticore will shoot some gas balls at you while you’re chomping the dragon. After that you run for manticore. And it will shoot out spikes at you. Right now the manticore boss is glitched it will swoop in look like it’s landing then fly back up in the sky. So you’ll want to try and end it with the manticore as quick as possible. Stims will help your Rex not KO in the boss fight