Duration: until expended or 10 minutes per caster level; (2hour and 30 minutes) at 17th level or 3 hours at 20th

While this spell is in effect, you can use your reaction to absorb a spell that is targeting only you and not with an area of effect. The absorbed spell's effect is canceled, and the spell's energy (not the spell itself) is stored to power spells of your own. The energy has the same level as the spell when it was cast.

Once the spell is cast, you can absorb 1d4+6 spell levels (rolled secretly by the DM). The level of each spell you absorb is subtracted from the total. A spell cannot be partially absorbed.

You can convert energy stored into spell slots to cast spells you have prepared or know. You can create spell slots only of a level equal to or lower than your own spell slots, up to a maximum of 5th level. You use the stored levels in place of your slots, but otherwise cast the spell as normal. For example, you can use 3 levels stored as a 3rd-level spell slot. You must have at hand (and expend) any material components required for the spell.