Weave rift

User creates a rift in the weave, allowing the user (and anyone he desires within sight) to push past their usual spell slots and use as many as they need. Characters who push past their regular spell slots, however, get 2 points of exhaustion when the rift closes or the rift stops effecting them (if the rift can't see the player) or for some other reasons. The rift appears as a purple-blue rip in the air. Those that step into it are transported to the astral plane for the duration of the rift. When going to the astral plane in this manner, the character is unable to cast any but the most simple spells (level 1 - 2) with the normal amount of spell slots