So we've tried this a couple times now and it has been a hit. This is a Mexican stand-off style game where only one person wins. There is no second place.

Start with a standard table draft. We have tried 2x packs of 9 cards however I think that 3x packs of 6 is probably better.

Build the standard 15 card decks. Usual mulligan rule applies. Player 1 does not draw. The first player to get a kill wins.

The only rule change is related to Mill. Mill is only a valid win con if a mill piece is played (this includes Clear the Mind). If no mill cards are played and a player decks out naturally, the game is a stalemate. This is to prevent turtling.

Some interesting gameplay has emerged, there is no risk of a crackback from the other player so going for the kill is highly incentivised, reducing the occurence of board stalls. Denying kills has also happened, Van played Stab Wound on Jerry's Arboreal Grazer and then I killed the Grazer with Flame-Blessed Bolt before his turn so Van didn't get the W.