Metapod and Kakuna are renowned for their hard shells, but are far from invincible; Pidgeot and Fearow drop them onto rocks and break them with relative ease. This is not the case with Pupitar, however, for those few Skarmory brave enough to try and eat them soon find that Pupitar more than live up to their reputation as a virtually indestructible pokemon, often beaten but never slain.

The earth's atmosphere, which burns up meteors so easily, is equally incapable of harming Pupitar. Some say they climb into space with their rocket propulsion to search for a better mountain than their decaying Mount Silver, and quite a few have developed craters from these strange, armored pokemon. It is lucky for the world that they are still outnumbered by even the endangered Torterra, so that mountains continue to be born faster than Larvitar can eat them. Others merely claim that they do this because one must see the world to rule the world, and every Tyranitar, like its name implies, strives to rule the world. Although ethics obviously prevent direct testing, eyewitness reports imply that Pupitar can also survive dynamite and even nuclear explosions.

It is odd to think that Pupitar, so expertly camouflaged against Mount Silver's terrain that few among the trainers great enough to enter notice them at all, even bother to hide. Some speculate that they once had natural predators, who have since went extinct. Others claim that they hide from the fratricidal violence of other Tyranitar, for the only thing which can break a Pupitar is a Tyranitar, and Pupitar only evolve once they are strong enough to smash through their own cocoons.