Void calling

As you extend your arms forward, your hands clasped together, a small ball of dark energy forms in your hands. You mumble incoherent, words in a dead language. Your eyes become black and for the duration of the spell you can only see the energy emitted by any creatures in a radius of 160ft centred around you as long as they would be in a direct line of sight. For the spells duration every time a creature attacks you they will be met with a dark ray of corruption and power giving them disadvantage and taking 2d8 Necrotic + your spellcasting ability modifier and 1d10 psychic damage. To cast this spell you must role a con saving throw. If you role higher than 14 you succeed and can cast it. For the duration of the spell any creature attacking you must role a con save as well. To succeed they must role 15 or higher. On a failed save the creature takes 2d8 necrotic damage + your spellcasting ability modifier and 1d10 psychic damage. On a succesfull save save they take only half as much damage