5e SRD:Black Tentacles
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|This material is published under the OGL|
|Casting time:||1 action|
|Components:||V, S, M (a piece of tentacle from a giant octopus or a giant squid)|
|Duration:||Concentration, up to 1 minute|
Squirming, ebony tentacles fill a 20-foot square on ground that you can see within range. For the duration, these tentacles turn the ground in the area into difficult terrain.
When a creature enters the affected area for the first time on a turn or starts its turn there, the creature must succeed on a Dexterity saving throw or take 3d6 bludgeoning damage and be restrained by the tentacles until the spell ends. A creature that starts its turn in the area and is already restrained by the tentacles takes 3d6 bludgeoning damage.