Alter Terrain

You touch the ground and change the terrain within up to 120 feet, centered on yourself. It becomes difficult terrain for every creature except the caster. This does not affect the inside of buildings or other constructed terrain. The caster chooses a terrain: Arctic, Coast, Desert, Forest, Grassland, Mountain, Swamp, Volcanic, Underwater, Urban, Underdark, or another terrain represented in the world your character resides in. The spell creates minor alterations to the land to resemble the chosen terrain. When the spell ends, the terrain returns to its original form and is no longer considered difficult terrain.

When you lose concentration, the terrain created by the spell persists until the end of the one hour duration, instead you are simply effected by the difficult terrain like normal.