Word on the street…
The wilderness is a result of the last god wars. It is mostly barren of life, and what life remains is overtly hostile. Littered with undead, demons and foul creatures, the wilderness is a place for even the bravest of heroes to avoid.
With the large number of demonic and undead creatures roaming about, it is wise to assume that Zamorak is the primary god of the wilderness.
-A cult attempted to summon a great, ancient beast in the wilderness. This beast was only partially summoned. It now roams, in an incorporeal, form siphoning souls from both the living, and dead.