Summon Greater Demon

level 4 - 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 1 CR 5 demon, friendly (CR +1/lvl).

Warlock

Wizard

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