Capture Soul

You touch a dead creature that has been dead for no longer than 10 days and capture their soul, trapping it within the object used for the material component of this spell. The raise dead and reincarnate spells can be cast on the object to revive the creature, forming a new body for it as described in the reincarnate spell in both cases. While the soul remains within the object, days spent do not count against the time limit of resurrection spells.

When you cast this spell, you can instead choose to siphon all of the power from the soul. Instead of being trapped within the object, the soul is completely consumed, and you regain hit points equal to 2d6 + your spell casting ability modifier. Also, you regain the spell slot used to cast this spell, but the new spell slot is 2nd level.

An object containing a trapped soul can be sold to vendors in cities for 500 gp. It can also be placed in a Soul Battery, which is a machine specifically made to siphon mana from the soul, which generates mana from it over a period of 40 years.