You draw on the ambient magical power of the world, artificially strengthening your own reserves. Until the end of your next turn, you temporarily gain one 2:nd level spell slot. The spell slot gained this way may be used to cast a spell that you know other than Zaalbar's Spellbolster with a casting time of 1 action, 1 bonus action or 1 reaction. However, the enhanced spell slot is unstable -- if you do not use it before the end of your next turn, it dissipates harmlessly.

When cast at higher levels, the temporary spell slot gained is similarly increased in level, up to a maximum of 9:th level. For example, casting Zaalbar's Spellbolster at 3:rd level would create a 4:th level temporary spell slot. Each level increase doubles the material costs involved -- casting Zaalbar's Spellbolster with a level 2 spell slot costs twice as much as casting it at level 1, casting it at level 3 costs twice as much as casting it at level 2, and so on.