A sudden death cube
Objectively the best version

Basic Overview:
1 Life
15 card deck size
Drafted in a 3x3 grid
See here for the original: https://cubecobra.com/cube/list/sob
See here for a more in-depth explanation: https://cubecobra.com/cube/overview/mysdc

My changes:
No losing by decking; If you're out of cards just stop drawing. The game can end in a draw.
First player does get to draw, but Second player gets a treasure token.

I tried to aim for a much slower style of SDC. Many games in other variations simply end without one player ever making a meaningful decision. To me, the point of the Sudden Death Cube is to get right into the action, so dead games defeat the whole purpose.