You can cast helpful spells that remain dormant until activated.
Benefit: A dormant spell can only be cast on a willing target. Dormant Spell cannot be used with area of effect spells. When a dormant spell is cast, the effects upon the targets are suppressed until a later time when the spell is activated. Activating a dormant spell requires a standard action by its caster (which provokes an attack of opportunity but is not considered spellcasting), at which time the spell effects take place on its original targets even if they are no longer in the normal range of the spell. Once activated, the effects persist as if the spell had just been cast. When you replenish spells, any dormant spells you have cast are lost.
Level Increase: +1 (a dormant spell uses a spell slot 1 level higher than the spell’s actual level.)
Example: Tom the wizard casts a dormant haste on his four companions while in camp. No effect takes place at this time. Later in a pitched battle, Tom takes a standard action to activate the haste spell. Tom and his four companions are now hasted for the normal duration of the spell no matter where they may be when Tom activates the spell. Even if a new fifth companion happens to be standing near Tom, the new companion would not be affected since he was not a target of the spell when it was cast.