Soul Cage

[ Cage des âmes ]
level 6 - necromancy
Casting Time: 1 reaction, which you take when a humanoid you can see within 60 feet of you dies
Range: 60 feet
Components: V, S, M (a tiny silver cage worth 100 gp)
Duration: 8 hours

Description not available (not OGL).
But here is a summary:

Snatch a soul to regain hp, ask it a question, get advantage to a roll, or see a place it saw in life.
Warlock
Wizard
Xanathar´s Guide to Everything
  1. DnD 5e Spells › Soul Cage