You and your opponents have descended into the poisonous dross pits, pitted into battle for cheap amusement- only one of you will make it out alive...

This is a Peasant cube explicitly inspired by @ryansaxe's Autobattler cube. Each round, players will follow the basic Draft-> Build -> Fight loop of that cube, constructing and shaping a hand to battle with. Cards have been selected to get players into interesting interactions and game states quickly.

This is modified from Ryan Saxe's ruleset to slightly simplify and as the cube doesn't need to emulate an autobattler so closely for my own personal taste.

Game Pieces
A copy of the cube list
 
each player needs
At least one Treasure token
3 copies of each basic land
A way to track their lifetotal
1 poison tracking card — you can also just track with pen and paper.
Tokens or postits

Setup
Shuffle the cube.
Give each player 7 random cards from the cube face down. These form the players' starting pools.
Give each player a Treasure token. Treasure can be used in a battle or to open a new pack while drafting.

Playing the Game
The game consists of a series of rounds. Each round has three phases: Draft -> Build -> Battle. When a round of 3 matches is over, the hand and treasure limit (represented by the energy card) is incremented by one (see image)

The first draft phase of the game is skipped so players can get right into building with their starting pool.

Build
Before battling, players privately prepare a starting hand from their pool and select 3 basic lands of their choice which will start in play in the upcoming battle. The starting hand size for the battle starts at 3 and increases by 1 after every round of 3 matches

Once all players are ready, pair players to battle. If it's the first battle, play the person sitting across from you. In each round, each player should play each opponent once- find a way to choose randomly, I trust you can figure it out, but the player making the random "rolls" to choose should change each round.

Battle
Battles are best-of-1, 1v1 matches of Magic with some modifications.

First and foremost, some game objects are persistent: they carry over from battle to battle. However, any effects on persistent objects will end when a battle does

Persistent Objects
Treasure tokens up to the current hand size (so 3 in round one, 4 in round two, etc)
Poison counters

Battle Rules
Starting hand size and maximum hand size is 3.
Starting life total is 10.
Players' start with 3 basic lands of their choice on the battlefield.
Neither player has a library, and hence do not lose as a result of being unable to draw a card.
The player with the most poison counters chooses play/draw. If players are tied, choose randomly.
Conceding is not allowed because Treasure tokens created during a battle persist afterwards.
A draw is treated as a loss for both players.
The losing player(s) gets poison counters corresponding to the current round (see table)
When all players have finished battling, that is the end of a "round". At the end of each match, deal 3 cards from the cube in front of the players. The winner picks one to add to their pool, then the loser picks, then each player is given a Treasure token. The remaining card is returned to the cube

Draft
Deal a "pack" of 5 cards to each player.

Then, each player can take any of the following actions any number of times:

Draft Actions
[buy] Swap a card in their pool with a card in the pack.
[re-roll] Pay a treasure to shuffle their pack back into the battler and open a new pack of 5 cards.
When a player is done drafting, they move to the build phase.

Determining a Winner
Players are eliminated whenever they have 10 or more poison counters. When there is only 1 non-eliminated player, they are the winner.

What Happens When A Player is Eliminated
When the first player is eliminated, they become The Ghost and lose all their poison counters. They continue to play as normal until a second player is eliminated. Once a second player is eliminated, the remaining two players will continue playing rounds as normal but always battling each other until there is a winner.

The game cannot end with two players getting eliminated at the same time. If that were to happen, those players are both set to 9 poison, and go into a sudden death loop.

Sudden Death
The game pauses until sudden death is over. Players in sudden death alternate between building and battling until a player is eliminated. If for some reason neither player can beat the other with their pools, all players continue to the next round.

Its still new, untested, feedback welcome