Tremor Trap

You cause a tremor in a location you specify within range, Until the spell ends, in a 15-foot-radius the ground erupts. Each creature other than you in that area must make a Dexterity saving throw. On a failed save, a creature is knocked prone. If the ground in that area is loose earth or stone, it becomes difficult terrain until cleared, with each 5-foot-diameter portion requiring at least 1 minute to clear by hand. As an action on your next turn, or until the spell ends. You cause the loose ground to explode with stone rubble ending the spell. Each creature in the area plus 5ft around the original spell must make a Dexterity saving throw. A target takes 2d8 bludgeoning damage on a failed save, or half as much damage on a successful one. 

If cast in terrain where there is fire, acid, ice, poison, or traps. Targets take an extra 1d4 of the damage type plus anything the object normally would apply and sets off the traps.

At Higher Levels. When you cast this spell using a spell slot of 2nd level or higher, the damage increases by 1d8 for each slot level above 1st.