Grenzo's doomsday machine (EDH / Commander)

Paths to victory in order of likelihood:

1. Get infinite mana, spam deck with Grenzo, combo out for infinite damage. Most of the creatures are power 2 or less, and the lords, Goblin Burrows, and especially Cloak and Dagger help the rest ETB off a buffed Grenzo.
2. Early Doomsday stack. See description below.
3. Goblin beats/internal synergies. Deck sports a goblin subtheme with 17 plus Grenzo. Lords and token generators tend to beef up the team enough to have a little board presence, with the possibility of hitting the right stuff to overwhelm with the beats. Also has a small utility package to take advantage of Matron and Harbinger, which is actually playable here because Harbinger into scry effect into Grenzo activation is good. The cards that make infinite damage are also good when they can't go infinite. AGGRO!!!!!!

Combos:
Grenzo+Ashnod's Altar+Soldevi Digger+ETB token generating creature=infinite goblins and colorless mana; if Murderous Redcap is involved gg.
Ashnod's Altar+Nim Deathmantle+ETB token generating creature/Murderous Redcap=ditto
Phyrexian Altar+Mikaeus, the Unhallowed+Workhorse=infinite red and black mana
Add Purphoros/Blood Artist/Flayer of the Hateboud to any of the above=infinite damage
Mikaeus+Murderous Redcap+any sac outlet=infinite damage

Doomsday stack (listed top to bottom so Workhorse is the bottom card):

1. [anything, probably some kind of control tech]
2. Zealous Conscripts
3. Mad Auntie/Goblin King/Goblin Chieftain
4. Kiki Jiki, Mirror Breaker
5. Workhorse

Just need 2BBB for infinite hasty creatures assuming Grenzo is on the field and none of ZC, KJ or WH are in hand. Cast Doomsday with the BBB, use the 2 to trigger Grenzo, ETB Workhorse. Remove two counters from Workhorse to activate Grenzo, ETB Kiki Jiki. Tap Kiki Jiki copying Workhose. Remove all four counters from the copy (or two from the original and two from the copy) to ETB a goblin lord. Grenzo is now 3/3. Use final 2 to ETB Zealous Conscripts. Swing for win.

Goblin Toolbox:
Goblin Welder (reanimate artifacts)
Stingscorger (bounce creatures)
Outrage Shaman (shoot creatures)
Goblin Ringleader (draw/scry)
Tuktuk Scrapper (artifact removal)

Artifact recursion subtheme:
Welder and Daretti can both get nuts with the likes of Clone Shell, Brass Herald, and Duplicant, which are also stellar Grenzo targets. Sacing a tapped Mana Vault/Grim Monolith/Basalt Monolith for one of those is fun. They also recur destroyed combo pieces.