Summon Lesser Demons

[ Convocation de démons mineurs ]
level 3 - conjuration
Casting Time: 1 action
Range: 60 feet
Components: V, S, M (a vial of blood from a humanoid killed within the past 24 hours)
Duration: Concentration, up to 1 hour

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

Summon 2 CR 1 demons 1 to 8 CR 1/4 demons, unfriendly (nbr of creatures/lvl).
Warlock
Wizard
Xanathar´s Guide to Everything
  1. DnD 5e Spells › Summon Lesser Demons