The first draft of my sudden death cube is now up. The cube is based on (https://cubecobra.com/cube/overview/z04), but with cards from my collection. Version 1 tries to approximate the original cube on a card by card basis, but future versions may diverge slightly.

The small size of the cube allows for a very tight color pie. Right now the loose plans for each color are as follows, but can be improved. Generally speaking, 3+ drops are expected to be game-ending if unanswered.

• White: Life gain
• Blue: Tempo/Stall, card selection
• Black: Painful to attack, and for opponent block
• Red: Go Wide, Sweepers, Burn
• Green: Stompy, Trample, Counters

Some notes, pre-playtest:

• Is Aven Riftwatcher too bomby for 3 mana? Is 4 life gained too much for having it be answered?
• The original cube uses moment of craving instead of Pharika's Cure and tends to prefer -X/-X over damage for black's removal. Black is supposed to be high-risk high-reward, but are the double pips on Cure too much for the effect?
• Red's sweeper identity is a little odd given red wants to go wide, but I don't have good sweepers at the moment anyway.
• It isn't clear how the payoffs and enablers should be distributed for green. I like the idea of stompy, vertical threats and creature protection, so counters work nice. Definitely like the idea of modal creatures that can be played earlier or later for value, with wincons being either a big beefy trampler or creatures that give trample to creatures with counters on them. What's the balance?
• Colorless spells are contention. Fountain is intersting in that it takes up a land slot so it's very costly in deck construction. Apparently Environmental Sciences plays well. Would like one mill/decking focused card at colorless. Literally clueless on the play patters for grindclock, getting it down turn 2 is risky but is later too late? I like the wall defender form Strixhaven, but is it okay for every color to get access to a one drop wall? Is having to pay for that mill too much?
• Arrogant Poet seems to be what I really want for black; fragile creature but can be game ending if you can get it in the air on turn 3.

Possible Subs once I acquire copies:

• Grindclock -> Feldon's Cane (Anti-decking tech, plus get your spells back, seems like a fun play pattern)
• Some white one drop -> Alseid of Life's Bounty (just opened a copy right after finishing v1 of the cube lol)
• Goblin Instigator -> Hordeling outburst (really want to support going wide with red to get around all the available 0/X blockers)
• Puncturing Light -> You Hear Something On Watch (The OG cube uses Immolating Glare to kill attackers. Puncturing Light killing most of the blockers in the format might be too good. You Hear Something On Watch will deal 5 to an attacking creature which should be good enough to kill almost anything in the cube, and also allows you to buff the board on offense.)
• Elvish Mystic (or Wildwood Tracker) -> Arboreal Grazer (I want green to have a ramp option at the 1 drop, and like Grazer more than Mystic in that role. Is there a world where both get played alongside Wall of Vines?)