Benthos Lock

5th-level transmutation (water/earth, gravity)
Casting Time: 1 action
Range: 90 ft
Components: V, S, M - Small container of water and lead
Duration: Concentration, up to 1 minute
Area: 30-ft-radius sphere (choose a point you can see)

You intensify gravity toward the seabed (or ground) inside the sphere.

• Ground in the area becomes clinging mire and pressure increases; the area is difficult terrain.
• Creatures that start their turn in the area must make a STR save. On a fail, their Speed becomes 0 until the start of their next turn and they sink 10 ft if in water; on a success, Speed −10 ft for the turn. If the creature's speed becomes 0 in the mire, they become restrained for that turn.
• Flying creatures that start their turn in the area must succeed on a CON save or descend 20 ft (speed not reduced on success).

At Higher Levels. Radius increases by +5 ft and the descent/sink by +5 ft for each slot level above 5th.

Cavitation Verse: Triggers (STR or CON fail, per creature type).