HOW IT WORKS
Three verbs. Everything else is consequence.
1. Open
Click a square. If nothing is under it, it shows how many bombs are touching it. If that number is zero, the whole empty region opens at once and rolls outward.
Your first click is always safe. The board is laid after you choose, so an opening move can never kill you.
2. Flag
Shift-click or right-click a square you believe is a bomb. A flag is your claim about a square, not the truth, and the game never tells you whether you were right until it matters.
3. Bank
Everything you open adds to the cart. The cart is not yours until you send it up. Hit a bomb and the cart is gone; the vault is never touched.
The five bombs
They do not all do the same thing, and you cannot tell them apart until one goes off.
The little one
Ends your descent. The ordinary one, and the most common.
The fat one
Takes every bomb touching it with it. Opening one in a crowded corner clears half the board and all of your cart.
The sleeper
Nothing happens when you open it. It goes off when the round ends, and it takes the cart of whoever woke it.
The shifty one
Moves when you open beside it. It will only ever move somewhere that leaves every number you have already seen true, so your working is never wrong, only out of date.
The dud
Coughs. That is all it does. It still counts toward every number around it, so it is never free information.
Blow your mine
Once per descent, detonate every bomb you flagged. Right flags pay double. Wrong flags cost. The move is scored on how well you read the board.
Playing against someone
Open a game and share the link. They take the other podium and you both work the same grid. Everything either of you opens, both of you see, marked by who found it.
Your carts are separate. Their bomb is not your bomb: if they go out, you carry on alone with everything they uncovered still on the board. The question the whole game asks is whether the square you are about to open is worth what it tells them.