Skill · no luck
Hex
On an 11×11 rhombus you connect two opposite sides. There is always a winner.
How to play
Player 1 connects left to right, player 2 top to bottom. Place stones until you have an unbroken chain. A draw is impossible.
Stake 1 BT per player. Winner takes it, draw refunds both. You have 24h per move in async — miss it and you lose the match and your stake.