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Grease

1st-level conjuration

Casting Time: 1 action
Range: 60 feet
Components: V, S, M (a bit of pork rind or butter)
Duration: 1 minute

Slick grease covers the ground in a 10-foot square centered on a point within range and turns it into difficult terrain for the duration.
When the grease appears, each creature standing in its area must succeed on a Dexterity saving throw or fall prone. A creature that enters the area or ends its turn there must also succeed on a Dexterity saving throw or fall prone.