Olgoi-Khorkhoi

Notes:

 * Spawns around (J-4).
 * Time spawns between 1 hour 30 minutes to 2 hours.
 * Does not require any normal worms to be killed for it to spawn.
 * Alternates between casting a spell (Stonega or Stone II) then using Sandspin, every few attack rounds.
 * Easily soloable by most level 75 jobs.
 * Immune to Silence (Tested with automaton; Every cast failed)
 * Has high Spellcasting interruption rate decrease, but it is possible to interrupt his casting via regular hits/WS. <10% chance to interrupt, gathered from multiple spawns.

Historical Background
The Olgoi-Khorkhoi is the local name for the Mongolian Death Worm.

It is said to be red in color, and is sometimes described as having darker spots or blotches. Sometimes it is said to have spiked projections at both ends. The Worms are purportedly between 2 to 5 feet long and thick bodied. The worm can supposedly kill by spitting sulferic acid as well as through electric shock.

The Mongolian name is олгой-хорхой (olgoi-khorkhoi) where olgoi means large intestine and khorkhoi means worm, so the full name means "intestine worm". The name refers to the Death Worm's appearance, which is reported to resemble the intestine of a cow.