Ray of Mayo
"I cast Ray of Mayo!"
As much as neckbeards love to play D&D so do they also love to fap. The problem is that doing the latter while doing the former can be alienatingly creepy if not thoroughly disgusting to their fellow players, given the ratio of hambeasts to gamer-girls who comprise the bulk of the gaming community. Blurring the lines between D&D and fapping sits "The Book of Erotic Fantasy"; an expansion of the d20 ruleset where players are encouraged to explore this taboo combination with their peers. Of course it didn't take long before /tg/ felt the need to add its own flavor to this salty puddle. Thankfully, however, the creations spewed forth were few and far between - such as a device for giving the Tarrasque a gender and milking its prostate for science, the Living Midnight Bliss, and most recently the Ray of Mayo.
Ray of Mayo is a 5th level Arcane spell that does exactly as its name suggests - it fires a ray of thinned mayonnaise - however, not in the manner one would expect. The spell itself targets a living enemy, who in turn fires the ray back at the caster, splattering them in the face and blinding them until they wipe the tangy goo from their eyes with a move action. The target of the spell, though, must make a Fortitude save equal to the caster's level + Wisdom modifier or be instantly Exhausted and stay as so until they rest uninterrupted for a half-hour. If a target is hit by multiple RoM spells he takes 1 Constitution damage for each failed save after the first.
In addition to being able to cast arcane spells, the caster must wear a ball gag and make jerking hand gestures in the direction of the target, must remain stationary once the spell is cast and take the creamy blast in the face (or else the spell fails) and must be completely unashamed about using such a spell ripe with sexual innuendo. On the other hand, the mayonnaise produced by the spell is delicious, hints of pineapple and goes great on a sandwich.