Short: a fire wyvern
Long: A fire wyvern is here, eyes flashing menacingly.
Extended: Standing nearby radiateing immense heat, this wyvern seems to give off blasts of hot air as it slowly flexes its wings , shifting its weight between its two legs, talons flexing testily. At the end of its long, sinewy neck rests a massive head, two large horns protruding forth from its thick skull, and once smaller one from the back. Eyes that look like shimmering ruby eyes glint as the light glances across them, bringing notice to the long, sharp teeth that jut out from its snout. Wide, leathery wings stretch out from its shoulders in the place of arms, and a long tails swishes and thumps the ground irritably, the spikes on the end of it gouging the ground and producing molten lava wherever it strikes.
Enter: With a snarl and an fierce glare, a fire wyvern enters from the $DIR.
Leave: Wings flexing and sending a hot blast of air, a fire wyvern leaves to the $DIR.
Death: Horns broken and wings tattered, the corpse of a fire wyvern lies here, defeated .