Carnero

Notes:
 * Lottery-based Ornery Sheep spawn
 * Spawns on the second level of Vomp Hill, around the I-8/I-9 area, not only within area marked on linked map.
 * Spawn time is completely random; has been camped for over 6 hours without a spawn, has also spawned within 5 minutes of being killed.
 * Immune to Sleep
 * Substantially larger in size as compared to Ornery Sheep
 * Has ~350 HP
 * Katayama has a high drop rate, but is NOT 100%.

Historical Background
Carnero is the Spanish word for "sheep" or "ram".

Also, Carneros is a monster from the folklore of the Canary Islands (taken over by Spain). It was described as a giant ram with huge horns. It liked to go after children. [this account needs corroboration as only one internet source was found for it]