Toll of Force

By influencing the arcane powers that be, you imbue the attacks of your nearby allies with Auralmancy. You can select up to five targets you can see; each target gains an additional 1d4 damage for every nonmagical attack they make for the duration, and their attacks are considered magical.
You can cast this spell using a higher-level spell slot. For every spell level above 3rd, increase the damage by 1d4 and you can select an additional target for the spell.