Level 9 DiseaseBlinding Sickness

Often spread in tainted water, blinding sickness leaves its victims sightless.

Stage 0: The target recovers from the disease.
Stage 1: Initial Effect: The target loses one healing surge that it cannot regain until cured.
Stage 2: The target’s vision is blurred. Creatures beyond 10 squares of it have concealment.
Stage 3: Final State: The target is blinded.
Check: At the end of each extended rest, the target makes an Endurance check if it is at stage 1 or 2.
14 or lower: The stage of the disease increases by one.
15-19: No Change
20 or higher: The stage of the disease decreases by one.

Published in Dungeon Master's Guide, page(s) 49.