Cloak of Night

A spell with numerous applications, it creates a thin, grayish cloak of intangible energy capable of robbing air from a target or area. When you cast the spell, target a creature in range as the cloak appears around them; an unwilling creature must succeed on a Dexterity saving throw. Alternatively, the spell can be used to target a 5-foot radius circle on the ground (not affecting creatures in the circle). A creature affected by this spell can repeat the saving throw at the end of each of their turns, ending the effect on a success.

Any flames or other effects requiring air are immediately snuffed out by the cloak. The spell prevents creatures affected by it (willing or not) from being affected by vapors or other airborne dangers, such as the deadly effects of cloudkill. A willing creature has enough time to take a deep breath to avoid suffocating while under the effect of this spell.

An unwilling creature affected by this spell must make a Constitution check at the beginning of their turn; they are considered to have a number of rounds of air equal to the difference between the number rolled and 10 (e.g. a creature rolling a 16 on their check would have 6 rounds of air remaining). If a creature rolls below 10, they begin suffocating at the beginning of their next turn.

This spell prevents verbal utterances altogether, including verbal components of spells.