Mines
A grid game where each safe tile you reveal lifts the multiplier, and you must cash out before uncovering a mine.
Mines is played on a grid, usually 5x5 for 25 tiles. You decide how many mines are hidden, then flip tiles one at a time. Every safe tile pushes the multiplier higher; you can cash out whenever you like, but landing on a mine loses the stake.
Where the mines come from
Mine positions are locked at the moment you bet. Most provably fair versions shuffle the 25 tile positions with a series of floats, in the Fisher-Yates manner where each float selects one of the positions still left, and treat the first positions drawn as mines. A complete shuffle can consume up to 24 floats, more than a single HMAC output holds, so the cursor advances through several HMAC rounds.
What verification proves here
With the grid fixed at bet time, you can confirm afterwards that each mine sat exactly where the casino reported and was never moved in reaction to your clicks.
Odds example
Three mines among 25 tiles give your first pick a 22/25 chance (88%) of being safe. Two safe picks in a row come in at 22/25 x 21/24, roughly 77%. The multipliers track these probabilities less the house edge.