Chaotic Form 2014

You cause the form of a willing creature to become malleable, dripping and flowing according to the target’s will as if the creature were a vaguely humanoid-shaped ooze. The creature is not affected by difficult terrain, it has advantage on Dexterity (Acrobatics) checks made to escape a grapple, and it suffers no penalties when squeezing through spaces one size smaller than itself. The target’s movement is halved while it is affected by chaotic form.

When you cast this spell using a spell slot of 5th level or higher, the duration increases by 10 minutes for each slot level above 4th.