The diet class of Vivosaurs vary by the Vivosaur. This page is about the carnivorous Vivosaurs only. Piscivores are treated as carnivores in the Fossilary.
Only Carnivorous Vivosaurs are allowed to participate in the Ribular Battle Royale tornament. Since a fair amount of large carnivorous Vivosaurs have effects that hinder allies while they're in the SZ, look into smaller carnivores to help support your team. (Also be aware of when your opponent's Vivosaurs change positions.)