Aebon'Zurr's True Strike

You point a finger at a target in range. Your magic grants you a brief insight into the target's defenses. You have a +1 to your next attack roll, and the target creature has a -1 to the next saving throw your force it to make. At the begining of each turn, if you have not hit the creature, or that creature has not failed a saving throw you force it to make, you gain an additional +1 to your attack roll, and the creature has an additional -1 to its saving throw that you force it to make. The spell ends once you successfully hit the target, or once the target fails a saving throw you cause it to make.

At Higher Levels: You may allow one other friendly creature of your choice to also gain these benefits against the chosen enemy at 5th level, and then a second friendly creature at 11th level, and a third at 17th level. Each friendly creature that hits the target, or makes the target fail one of its saving throws, can no longer benefit from this spell.