The Lost Lands

Beyond the known boundaries of the Span lies a realm shrouded in malevolent obscurity—the Lost Lands. This forsaken expanse is a testament to pestilence, a vile miasma that corrodes not just the flesh but also the very essence of one's being. Throughout the ages, the valiant Sons of the Seventh Seal have undertaken perilous expeditions into this accursed domain, their unwavering purpose to unveil its secrets and banish the encroaching darkness.
However, a formidable impediment halts their advance—an impenetrable barrier known as the Miasmic Blockade. Here, the malignant pestilence swells to an unprecedented concentration, rendering their protective wards feeble and vulnerable. No explorer has emerged from beyond this ominous frontier, for once breached, the noxious vapors assail their defenses, accelerating their decay until none can return.
Through their annals, the Sons recount tales of valiant efforts, each attempt to breach the Miasmic Blockade met with fierce resistance from the land itself, as if the Lost Lands were sentient and guarded its secrets with a malevolent will. The barriers erected by the Seventh Seal have stood resolute, preventing the rampant contagion from spilling into the realms beyond.
Legends whisper of those who sought passage past the Miasmic Blockade, drawn by curiosity or driven by a sense of duty, only to succumb to the insidious corrosion of body and soul. The mystery of what lies beyond the impenetrable fog tantalizes the adventurous spirit but remains an enigma, shrouded in the desolation and peril of the Lost Lands.

Locations

The 

Negative Ebb: Every hour of travel, the party suffers 1 negative energy damage (to a max of 24 damage per hour), This damage is cumulative and doesn't cease until leaving the lost lands. The damage makes finding rest within the lost lands impossible. Wounds do not heal naturally within the lost lands for anyone other than chaotic evil outsiders. 
Positive Energy Lock: Any positive energy spell that is cast within the lost lands requires a DC 15 caster level check to succeed. On a failure, the spell slot is expended. 
Pestilence: Inhailed, Fort DC 16, 1d4 Con