Rock Dogs are completely immune to fire, and will not even flinch if attacked by an attack exclusively made of fire, such the flames of a Fire Bug or the presence of a Magmar. Riders atop Rock Dogs also share this ability. However, Rock Dogs are not immune to Lava and riders wearing a flammable pack item such as a Jetpack will still explode if attacked by fire.
When untamed, Rock Dogs will spit their fireballs at the player, dealing two damage, igniting any pack items they are wearing, and having the potential to infinitely stun the player until their eventual death.
Rock Dogs have a very precise hitbox for landing on them and taming them, making it incredibly difficult to properly get onto a Rock Dog who is not trapped in a one block gap.
When tamed, the player can use their fireball attack to easily dispatch of most enemies, burn specific objects, and even cook Cave Turkeys. Note that they do not grant any extra mobility other than its double jump unlike other mounts.
Cavemen can occasionally be seen riding tamed Rock Dogs, who will order them to shoot their fireballs at the player and move at incredibly high speeds. If the Rock Dog is relieved of its rider, they will be already tamed and will no longer attack the player.
- Rock Dogs are possibly one of the most dangerous enemies in the game when untamed. Their incredibly precise landing hitbox makes an attack from above very difficult, and facing a Rock Dog head-on will likely get the player stuck in an infinite loop of being hit by their fireballs and/or detonate any flammable pack items that they may be wearing.
- Because of this, the best way to deal with a Rock Dog is to throw an item at it from a safe distance.