Isla Mogila

Island of Death (1)
Inhabited by the vampire Richard Tremblay aka The Samurai of Wickedness (1)
The island bleeds (1)
At night, it is protected by all manner of fell creatures (1)
Including undead fey creatures (1)
Blood elves burn the clots of coagulated blood in honor of the god they call the Sanguinedeius (2)

The essence of the Island's power is that is a crucible for Sacrifice(1). Richard Tremblay sacrificed his soul to become the Samurai of Wickedness (1). The Blood Elves sacrifice their own to gain their power (1).

Sanguinedeius has the form of a giant leech (1c). The blood elves collect remnant statuary from other religions and deface their gods/heroes with the sign of the Leech, usually at the back of the neck (1c).

Captives of the blood elves are typically ritually exsanguinated by being lowered into a pit of holy leeches (1c).

The island was created by powerful beings of a forgotten age (1). Tremblay helped create the island along with his compatriots (1). He is not the only survivor on this end of time (1). Their plan helped secure their long term existences on this planet (1). Their work also helped quell world ending threats such as the dragon (1).

A great system of blood-aqueducts flows from the central volcano down four major arteries to the villages of the Blood Elves. They have capillaries that break off to supply smaller temples to Sanguinedeius. The blood that flows through the pipes is magical and consists of a mixture of dragon's blood, demon's blood, and pixie dust.