Fire procs are very very good, because they deal more damage and full refresh the more stacks you get. This means large fire stacks can deal MASSIVE amounts of damage when they tick. This build's goal is just to apply as many fire procs as possible as quickly as possible. The viral procs do take away from this, but their status effect boosts the damage of the fire procs even more, so it's a fair tradeoff. This build is also fairly cheap, with only four forma and no primed mods

update: [Galvanized Chamber]