The Isle of Hist

Located far west of Zazesspur, Hist had been avoided by sailors and explorers for years due to rumors of murderous, invulnerable creatures lurking in its jungles.

Geography
Lots of hills, lots of sand, lots of trees. Big fortress in the middle.

Inhabitants
Hist was uninhabited, save for the expected flora and fauna of a tropical island, until a wizard from an explorer's guild discovered a rift between the island and another world in the Material, Eberron. Word traveled to the artificer's guild led by Beaudefinadomdum Rickenrasst, who would bring his apprentice Lucian Attizar to explore the island and the rift.

Beau and Lucian made camp on the island and began to travel through the rift, bringing sketches and component parts of warforged with them. They attempted to reverse engineer the warforged and build prototype versions of their own.

Lucian quickly became secretive about his designs, and Beau discovered slain warforged and gruesome golem-like constructs using humanoid corpses combined with warforged parts in Lucian's laboratory. Beau was attacked by some of these abominations and fled the island, leaving Lucian to his experiments.

Over the years, the island was slowly filled with Lucian's creations. All manner of parts were gathered from living creatures and combined in macabre ways with magical constructs. These creatures were loyal to Lucian and enacted his will via an amulet that controlled their collective consciousness.

Lucian's Creations
The earliest of Lucian's warforged abominations were simply human cadavers that had been fused with warforged parts. Some still possessed organs, but critically damaged biological parts were reconstructed using the technology Lucian had studied and designed.

Abominations created by Lucian until his death included warrior animal-humanoid hybrids, all manner of warforged including those capable of spellcasting, a Fire Giant, and a Beholder.