Orb of Fire

Requires Attunement
(1) Action 2/day:
A creature in sight loses its fire resist/immunity
until the end of your next turn.
(2) Any magic user may use their casting action to
store a spell slot into this magic orb. The orb
inhibits creatures of the fire plane abilities
depending on the amount of spell slots stored this
way and its CR. When no spell slots have been
added to the orb within the last 2 rounds it
loses 1/10th (or 2) spell slots per round.