Black Bloom of Hadar

You open a wound in the world through which a fragment of Far Realm presence takes root. A thin fog followed by living darkness erupts from a point on the ground you can see within range. The ground in a 60-foot-radius, centered on that point, becomes a slick, writhing surface of shadowy flesh and grasping tendrils for the duration.

The area is Difficult Terrain and Lightly Obscured. Nonmagical light in the area is dimmed. At the epicenter of the spell, in a 15-foot diameter, a Maw is formed, an area Heavily Obscured by roiling black-violet mist, whispering shadows, and grasping tendrils.

When the spell appears, choose a number of creatures you can see equal to your spellcasting ability modifier, minimum of one creature. The chosen creatures aren’t targeted by the tendrils pulls and do not make saving throws against the spell.

A creature that enters the spell’s area for the first time on a turn or starts its turn there must make a Strength saving throw. On a failed save, the creature’s Speed is reduced by 20 feet until the start of its next turn.

If the creature fails this save by 5 or more, it is also pulled up to 15 feet straight toward the center of the spell.

At the end of each creature’s turn, if that creature is within 15 feet of the center of the spell, it must make a Strength saving throw. On a failed save, the creature is pulled up to 15 feet straight toward the center of the spell. If this pull moves the creature into Maw, the creature takes 8d6 Psychic damage.

When the spell ends, the living darkness withdraws at once, leaving behind cold stone, dimmed light, and the terrible certainty that something beneath the world briefly opened its eye.