(evil, extraplanar, giant)
Source: Shadow of the Storm Tyrant, pg(s). 86-87
The first known record of an Abaddon gigas dates to when Lamashtu captured and killed two of the Four Horsemen during her first conflict with the daemons. Their putrid remains oozed toward Abaddon's heart and merged with the body of a captured Thanatotic titan and perhaps some of the energy of the Oinodaemon to create the original Abaddon gigas, a hideous being of size beyond reason and composed of some of the multiverse's most powerful souls. This mythic gigas soon tore itself into countless pieces, each of which become a child known as an Abaddon gigas.
Abaddon gigas are asexual and can neither reproduce nor replenish their numbers. Planar scholars whisper that, when an Abaddon gigas is slain, its power crawls back toward the heart of Abaddon, where the original Abaddon gigas will reform once all its offspring have died.
A few Abaddon gigas serve the Four Horsemen, sensing in them some missing piece of their long-lost original selves. Most wander the wastes of Abaddon in search of something that they themselves cannot define and only Charon knows: they yearn for the Oinodaemon. Charon keeps this secret to himself and keeps a distant watch over the Abaddon gigas; it is unknown if he has an ulterior motive for this or not.
Abaddon gigas have nefarious reputations due to their terrible power, and few giant hunters, even plane-trotting ones, would willingly seek out an Abaddon gigas.