This powder resembles fine sand. There is enough of it for one use. When you take a Utilize action to throw the dust into the air, you and each creature and object within a 10-foot Emanation originating from you have the Invisible condition for 2d4 minutes. The duration is the same for all subjects, and the dust is consumed when its magic takes effect. Immediately after an affected creature makes an attack roll, deals damage, or casts a spell, the Invisible condition ends for that creature.
RollQuest summary Utilize action: you and each creature and object in a 10-ft Emanation from you have the Invisible condition for 2d4 minutes; it ends for a creature immediately after it makes an attack roll, deals damage, or casts a spell.
RollQuest ships the D&D 2024 SRD as a content pack, on a 5e character sheet that does the maths - roll from the sheet and let the numbers work themselves out. Free to start.