Magical Bond

You are bonded with a trinket item which you choose upon receiving this feat (examples: arcane focus, gnarled branch, holy symbol). This item is imbued with some amount of magical power, which you can use to power your own spells.

Once per short rest, you may focus on the bonded item and siphon the energy from within it. If you do so, you may choose a spell from your class' spell list which you have already cast since you last long rested. That spell may once again be cast without using a spell slot. The magic taken from the bonded item dissipates if not used before the next short rest.