Arcane Feast

You gain the preternatural ability to harvest the arcane essence off the bodies of your enemies.

When you slay a creature that has the spellcasting ability and at least one spell from the sorcerer spell list, you obtain a number of spells of your choice from the creature’s known spells whose total levels are less than or equal to your Intelligence modifier. You can only take spells whose levels are no higher than half your level (rounded up).

You can take a spell multiple times, with each instance being consumed when used.

You can use this feature a number of times per day equal to your Intelligence modifier.

These spells last until you use them, and you can stockpile spells from multiple creatures over several days; however, after taking a long rest while you have spells retained in this manner, you must make a Wisdom saving throw (DC 10 + total level of spells retained). On a failed save, you gain a point of exhaustion and your Hit Point Maximum is reduced by the modifier added to the Save DC multiplied by half of your level (rounded down, minimum 1). Your hit point maximum recovers after a long rest, regardless of if you would fail the saving throw of this effect again - you will only be under the effect of the most recent penalty from this effect. The exhaustion suffered by this effect only recovers if you take a long rest without any spells stored, and can stack from repeated failed saving throws.