Arctozolt is a hybrid fossil Pokémon. It has a light-blue body with a snow-like patch on the top. Its body has blue fins with white patches on the ends and some spots. It has a mosasaur-like tail with a fin on top. It has two yellow hands. Arctozolt has a raptor-like head with closed eyes and a blue spot on each cheek. It produces mucus from its nose.
By shaking its freezing upper half, Arctozolt can generate electricity. It was known to live on ancient shores and preserved its food with the ice on its body. It allegedly went extinct because it moved very slowly, but this is likely not the case due to Arctozolt being combined from two separate Pokémon that each had their niches before going extinct.
Arctozolt, like its counterparts, may be based on the Crystal Palace Dinosaurs, a series of misassembled dinosaur sculptures displayed at the Crystal Palace Park. It may reference the statue of an Ichthyosaurus walking on land. In the case of Arctozolt, its top half appears to be based on a dromaeosaurid, while its bottom half appears to be based on an aquatic reptile, like a plesiosaur, mosasaur or ichthyosaur. It may have also been inspired by the chimera and similar mythological creatures, which was stated to have the features of different animal species, and is often interpreted as being scientifically constructed from different animal parts.
The Pokédex entries for all the Galar Fossils mention them being the cause of their extinction, which may be a reference to the outdated hypothesis that the dinosaurs were evolutionarily inert, which made them get bigger, stupider, and more sluggish, to the point they couldn't sustain themselves.
Arctozolt being unable to breed could be a reference to cross-bred animals, which are born infertile (unable to produce offspring).
Arctozolt may be a combination of arctic and volt or jolt.
Patchilldon may be a combination of パチパチ pachipachi (onomatopoeia for crackling), chill, and -don (common suffix in dinosaur names derived from the Ancient Greek word for tooth).