I play in a Precon league with my brother and his friends. We start the league off with a precon of our choice for 6 games. We are allowed to make upgrades based on how we placed in the last game, following a budget plan (adding cards that are expensive back to the deck if cut is fine).
Here is the breakdown per week:
Here are the decks picked for this league:
I picked Graveyard Overdrive because I love Modern Jund, 1 for 1s, and Tarmogoyf. My upgrade path was to rely less on putting Goyfs directly into play with Disa and more on making Tarmogoyf tokens. I found out that just making 1-2 Goyf tokens a turn and having a huge blocker was a pretty good plan. The first game I started pretty strong with some Goyf tokens but ended up getting taken out by Mahesh with the go wide plan that Riders of Rohan uses. That meant I was 4th which allowed for 12 changes. Since 1 for 1s are hard to get ahead with in commander, I wanted each top deck to feel more powerful so I started with some of the cards that I didn't think added to the plan. Playing natually seemed to grow the Goyfs so self mill wasn't needed. I took out cards like Stitcher's Supplier, Coram (kinda a pain on webcam), and Grisly Salvage. Some other cards I removed was Selvala, Rampart Growth, The Reaver Cleaver, Izoni, and Deathreap Ritual.
I liked the Siege-Gang Lieutenant so I added Siege-Gang Commander and Sling-Gang Lieutenant. Goblin tokens are fun! I added Decimate because it can blow up lots of things (and I had an alt art of it), Garruk's Uprising and Garna, Bloodfist of Keld for card draw, Oversold Cemetery for late game recursion, Cut//Ribbons, Flametongue Kavu and Ravenous Chupacabra for some creature removal. Also added Massacre Girl as a way to clear the board (looking at you Riders of Rohan!). Ophiomancer was added as a way to threaten larger creatures and Scavenging Ooze to eat up the graveyard when Mind Flayarrrs tried anything tricky.
The next game Taylor tried to win right off the bat with Mechananized Production on a mana rock on turn 3 so we ended up having to take him out quickly (thank you Mahesh for coming in clutch). I got a lot of value by making lots of Goyf tokens and then using Ziatora, the Incinerator to fling the tapped Goyfs for some direct damage. That gave me 3 swaps so I took out Anger, Bloodbraid Challenger, and Llurgoyf. My adds were Palace Siege (modular things rule), Massacre Wurm and Honest Rutstein. I really wanted to add Squee and Tortured Existence as a value loop but Tortured Existence refuses to be cheap! It will be a post league add when I don't have to stick with a budget I think.
For the 3rd game (currently the last one we have played), there was a lot of slugging between Mahesh, Justin and myself. We got to pretty low life totals while Taylor was just casting small creatures and did a little tutoring. We ignored him for the most part as he wasn't doing anything of note with just a Gonti's Aether Heart in play. He promised us that he couldn't loop it for infinite turns as it exiles itself. Turns out he didn't need infinite turns when he assembled his combo of Automated Assembly Line + Gonti's Aether Heart + Izzet Generatorium. Basically you pay 3 energy, get a 3/3. Gonti's Aether Heart gives you 2 energy, boosted to 3 by Izzet Generatorium. He just had infinite creatures instead! He then exiled the Heart and killed all 3 of us on his extra turn. It was wild.