Venomous Growth

You focus and reach out, connecting to the magical Ley Lines of the Earth surrounding you. The ground in a 20-foot Cube centered on a point you choose within range churns and sprouts forth bulbous flower buds and mushrooms. They burst open releasing green clouds of poisonous gas and spores. The area becomes Toxic and Difficult Terrain for the duration. When a creature moves into or within the area, it must succeed on a CON Saving Throw equal to your Spell Save DC or take (5d4)+SM Poison damage for every 5 feet it travels and become Poisoned for 1 Round. 

The transformation of the ground is camouflaged to look natural. Any creature that can't see the area at the time the spell is cast must make a Wisdom (Perception) check against your Spell Save DC to recognize the terrain as hazardous before entering it.

At Higher Levels: When you cast this spell using a spell slot of 4th level or higher the Poison damage increases by +(2d4) per spell level above 3rd.