The floor slopes downwards towards the far wall. A few doors are on the side walls.
|The floors and walls become magically covered in ice when one of the side doors is opened.
When a side door is opened, the floor becomes a slick sheet of ice and the far wall is covered in outward facing sharp icicles. All targets on the icy floor must make a DC 14 Dexterity saving throw or fall.
Each target that starts their turn prone on the ice may attempt to either stand up or stop sliding. Standing up requires a DC 14 Dexterity (Acrobatics) check with disadvantage. Stopping the sliding requires a DC 14 Dexterity (Acrobatics) check. If either fails, the target slides 30 feet towards the icicle wall.
Targets that are not prone may attempt to move at 1/4 speed with a successful DC 14 Dexterity (Acrobatics) check. Failure results in the target falling prone.
Targets that slide into the wall take suffer a +8 melee attack for 2d8 piercing and 1d6 cold damage. Targets that start their turn in the icicles take 1d4 cold damage per round. A target in the icicles may make a DC 8 Strength check to break the icicles out of them, halting the ongoing cold damage.
Targets in the icicles do not suffer disadvantage when trying to stand up.
The ice lasts for 10 minutes.
A spell such as Detect Magic detects an aura of evocation on the entire room.
A spell such as Dispel Magic permanently disables the ice effect on a successful DC 15 spellcaster check. Effects that suppress magic at spell level 5 or above suppress the ice effects for the duration of the effect, including any ongoing active ice effects.