Domain Expansion

Domain Expansion is an extension of your arcana source. It represents both your personality and your spellcasting style, so you can make your expansion look and sound how you want to match your character. Anyone outside the domain cannot see inside, and all magical and non magical attempts at seeing inside fail. It creates a 50ft radius dome, its center fixed at the casting point. (The domain expands from within you, but does not move with you)

The spell allows you to instantly land attack rolls against targets within the expansion. When targets are initially engulfed, they must succeed a Wisdom saving throw (your spellcasting DC). If failed, the following effect occurs:

Targets automatically fail saving throws against you inside your expansion, and its damage is reduced by (3d10 + spellcasting modifier) against a maximum of 4 chosen creatures within your expansion (You cannot be protected and still be attacked)

You can move instantaneously anywhere within your expansion no matter your speed, and you succeed any saving throws inside your domain.

However, your domain can be ended early by being destroyed from the outside, your domain has an AC 15, and (2d10 + spellcasting modifier) hit points. Also, if your domain takes 25% hit point damage in one 5ft area, a hole will be created that allows creatures to enter. Any creature that enters your domain after creation will not be effected by the spell. (Does not instantly fail saving throws or attacks, and you cannot instantly land attacks against the target) 

You cannot leave your domain while it is in effect, but you can stop the domain at will with a bonus action.

After your Domain Expansion ends, you must succeed in a DC 20 constitution saving throw to avoid the effects of exhaustion. If failed, you take 1 level of exhaustion, as the spell requires you to use your maximum concentration and power.