I was flying around in the Redwoods with my main Pteranodon, he was my favorite Pteranodon, we basically did everything together. I leveled him to really good stats. We were looking for a Megatherium as I heard they were really good. But after looking around and getting jumped by a Thylacoleo, I decided it was time to leave. I saw three Rhyniognathas, I heard they were dangerous so I stayed away, but I didn't know their aggro radius was so big, I flew as fast as I can, around rocks and trying to get them to attack Paracers, but that didn't work, I ran out of stamina and two Rhynios ripped my Pteranodon into pieces, I managed to escape, killing a Thyla with a metal hatchet, I crouched, thinking about how to escape, until a Rhynio attacked and killed me on spot, I didn't even get to run. Never go near the swamp, you can't outrun the Rhynios, and even if you do, another one will be waiting for you, ready to murder you.