Blood Rune

You stab into your own palm, drawing a rune on the ground around yourself. Once finished, the rune lights up and fills a 30ft area with a red mist. Any creature in the mist when cast or entering the mist must make a DC 15 Constitution Saving Throw. On a successful save, they take 1d8 poison damage, however on a failed save they take 2d8 instead.

At higher levels, the spell does 1d8 more damage per level.