Desperate attack

This spell burns half of casters body into blackish  meat, their stature stays intact however half of their body looks like you have caught level 8 fireball into your face. This affects your day to day tasks (you have blury  vision in one eye and your conrdination is bit funky). 

After the spell caster is half way through casting this spell they began to feel extreme pain in their dominant side of the body (dealing no damage) and they began to see small black orbs appearing in the room. After 9h their body gets set ablaze which will deal 10d4 fire damage and you have to make a con save of 15 or the ritual will be stopped, and if resumed over again the other side of their body will get burn as well giving them temporary (d4 weeks) of blidness. However when succeeded they continue the ritual with no further complications from this spell.

Once this spell succeededs it will create 250ft radius of pernament magical darkness in which you´ll be given devil sight and your body returns to normal (only when you are in this darkness), this darkness cannot be moved once casted and whenever someone dies in this darkness they turn into a zombie, ghost, skeleton or ghoul, roll d4 to see witch one it is. When an undead dies in this area their body turns to ashes. Creatures in the area of effect must make a wisdom save of your DC at the start and end of their turn if they are in it. Once they fail they will be able to make another save after 2 days have past. You are immune to this.

Verbal component: Just say bunch or random stuff, for inspiration: Romen the seventh god of the eight sun bellow the surface of my foot.

Somatic: you sit in one room and once per hour you stand up to do a little dance.