Irithix, Formless Contagion

Voidlord (Irithix must be your commander)
Split Second. Protection from everything.
If your devotion to {c} is less than 8, Irithix isn't a creature and loses Protection from everything.
Irithix enters the battlefield with {x}+1/+1 counters.

Whenever a source would produce mana, it produces {c}instead equal to Irithix's power unless its controller
pays that much life.
All colored mana sources deal damage to their owner
equal to Irithix's power when spent.