It was a paw, fully two feet and a half across, and equipped with formidable talons. After it came another paw, and after that a great black-furred arm to which both of the paws were attached by short forearms. Then two pink eyes shone, and the head of the awakened gug sentry, large as a barrel, wabbled into view. The eyes jutted two inches from each side, shaded by bony protuberances overgrown with coarse hairs. But the head was chiefly terrible because of the mouth. That mouth had great yellow fangs and ran from the top to the bottom of the head, opening vertically instead of horizontally. Instinct: to rip apart and devour entirely

• Rip to pieces

The magma ooze is an amorphous creature that appears to be an animate blob of smoldering lava. Found in or near active volcanos, magma oozes usually wait for prey immersed in pools of lava where they are completely undetectable as long as they don't move or attack. Once the ooze's sensitive tremor sense registers nearby prey, the creature leaps out of its hiding place with surprising agility and tries to engulf its victim in its burning body. Since the magma ooze is composed of burning hot lava, it is obviously dangerous to strike it with melee weapons or even unarmed. When a magma ooze is killed, its body cools down immediately and turns into a lump of solid lava rock, possibly getting the weapon stuck in it that was used to strike the ooze down. The magma oozes body will also cool down and harden when leaves its lava pond for more than several hours. In this case, the creature is petrified but can be brought back to life by immersing it in lava or a similarly hot substance like molten iron. Instinct: to burn flesh and bone

• Engulf and Burn