Crimson Suffering (3.5e Equipment)
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The Crimson Suffering is the quarterstaff used by Merihem, The Red Death. Though it's usually located on his own layer, the weapon sometimes finds its way into the Material Plane, usually in the hands of his most faithful. It is a +3 unholy, vampiric, weaking, wounding quarterstaff that when it deals damage to an opponent, he must make a DC 20 Fortitude save or be inflicted all diseases on the Contagion spell list, using the original DC for the secondary saves as well as a DC 20 Will save or be inflicted with insanity as in the spell.
Destroying this weapon can be done in two ways: either a wielder of the weapon can use it to kill Merihem on his home layer of the Abyss which is a very difficult thing to do; few have come face-to-face with Merihem on this home layer and walked away with their mind and body untouched.
The other way is easier to do but no less dangerous. A wielder of the weapon can take it to the center of the Positive Energy Plane and there bless the weapon by soaking it in pure water for one week while continuely praying to three good aligned deities for the purification of the weapon.
Upon destroying the weapon, Merihem becomes a weakened god for 100 years, upon which he can create the weapon again using his powers.