Amelok, Death's Breath

Partner with Asphodotal, Eye of Terror
Indestructible
When Amelok, Death's Breath enters the battlefield, place an infection counter on him
{t}: Proliferate. Activate only as a sorcery.
{p/b}{p/b}{p/g}{p/g}: Gain control of all permanents with
5 or more infection counters.
I spread through streets, silent and slow. Bringing fever and death, wherever I go. Rats and fleas may carry my might. Leaving cities empty, in endless night. What. Am. I?