The creature's appearance leads to its nickname of the fangbird or vampire lizard. However, they are not actually blood drinkers, usually feeding on fish, reptiles, and birds. There are also tales of dimorphodons gathering in flocks of up to nine creatures in order to bring down larger prey. In those cases poison their victim with their bites, then back off while it dies.1
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- Dimorphodon (extinct real-world animal) on Wikipedia