These cute amphibians are excellent for killing trilobites and gathering their corpses, since they:

* have a large damage multiplier on them

* gather black pearls in addition to the normal drops

* are fast enough to avoid and evade marine predators such as sharks

* will kill and gather trilobites in a single hit.

Additionally, they’re great for pre-scuba gear silica pearl diving, since they can act as a portable oxygen tank. Just be wary of sea scorpions stinging your diplocaulus while you are grabbing pearls, because it has extremely low torpor and could be knocked out.