Embrace the Rot by Endless Taverns.
I play a high level D&D spore druid who worships the rot as the culmination of the circle of life and death. He's also, due to our campaign turning us into the heirs of the Horsemen of the Apocalypse, currently wearing the mantle of the second horseman "Pestilence".
It's just... the song is perfect, it's his theme song now.
Wait, what?