Animate landscape

You animate the landscape, causing everything nonliving to come alive, at the cost of extreme mental strain. When you cast this spell, you start to chant for 1 action. In between the first and second action, all attacks made against you have advantage. For the second action you release a dome of energy, 50 feet in radius, centered around youself. Within the dome the landscape comes alive, causing the following effects:

• All terrain becomes dificult, but only to the enemy
• Every 5 feet the enemy moves they take 1d4+1 bludgening, Slashing, or piercing (your choice)
• All allies can move 15 extra feet
• When a melee attack is made by an ally, roll a d20, on a 11 or above, that attack has advantage
• Your AC is increased by 4, and all allies AC is increased by 2
• As an action every turn you can cause a swarm of objects attack a creature of your choice, dealing 6d4 + 6  bludgeoning damage
• As a action every turn you can cause a wall, or some other obstruction to appear to block any area. The wall has 10d10 + 30 hitpoints. It has immunity to pychic and necrotic damage, and resistance to all other damage types but Bludgening and force.

When the spell ends, the caster takes 1d10-2 damage per round the spell was active.

At Higher Levels: 

When you cast this with a 8th level spell slot, reduce the self damage to 1d8-2 per round. If you cast this at 9th level spell slot, reduce the damage to 1d6-2 damage per round.