Hearthpwn

Clicked this link because I legitimately forgot that Grim Patron was a neutral card.

I gave it about 6 games in casual.  Lost 4.  One thing I learned is that Spreading Maddness doesn't work with Grim Patron as I had hoped.  It can only target the single Patron, it won't target spawned patrons.  So, you have to ping is a time or two before you cast Spreading Madness for maximum effect.

Spreading Madness is a decent board clear though.

Patron is a playable deck in Warrior because Warrior has cheap activators. Death's Bite + Grim Patron + Inner Rage can let you jam 4 Patrons as early as turn 5.

Spreading Madness doesn't come anywhere near to being a way to make a viable Patron deck for Warlock. Even if we ignore the consistency issue, the absolute earliest you can go off with this deck is turn 7.

Sorry, this simply isn't going to work. Cards like Dread Infernal are not going to make Patron Warlock at all viable, as it won't even do anything unless you already have Patrons.

Haha awesome use of Spreading Madness!^^
However I would've absolute loved to see Floating Watcher and/or Hogger, Doom of Elwynn in there for more synergy with Spreading Madness and maybe Demonwrath or Wild Pyromancer for even more Grim Patron synergy!
Including Floating Watchers and Demonwrath would ofc make you wanna include Voidcallers as well ;)

Edit: Maybe even add in a Gurubashi Berserker for the lols with Spreading Madness^^