Uttering an infernal incantation, you summon a yugoloth from the Lower Planes. You choose the yugoloth’s type, which must be one of challenge rating 8 or lower, such as a canoloth or a dhergoloth. The yugoloth appears in an unoccupied space that you can see within range. The yugoloth disappears when it drops to 0 hit points or when the spell ends.

The yugoloth is unfriendly toward you and your companions. Roll initiative for the yugoloth, which has its own turns. It is under the Dungeon Master’s control and acts according to its nature on each of its turns, which might result in its attacking you if it thinks it can prevail, or trying to tempt you to undertake an evil act in exchange for limited service. The DM has the creature’s statistics.

On each of your turns, you can attempt to pay for the yugoloth's services. They'll usually ask for 100gp times their CR in payment. If they are asked for particularly complex or sensitive matters, they may ask for more payment (an example of such circumstances is requesting that they submit to a Planar Binding spell). If the yugoloth is asked to do something outside of this contract, it may choose to either ask for more payment or void the contract, becoming hostile once more.

Yugoloths are first and foremost greedy, so if another party offers the yugoloth a higher payment for equal or lesser services, the yugoloth will also terminate this contract and ally with their new employer. If this new party has access to this spell, they may cast it with the convinced yugoloth to start concentrating on the spell themselves.

If your concentration ends before the spell reaches its full duration, the yugoloth won't disappear if it has no deal with you. Instead, it acts in whatever manner it chooses for 3d6 minutes, and then it disappears.