Three pieces that agree on everything clear the line. That is the whole rule, and it is harder than it sounds.
Every piece carries a colour, a number and a shape. Pop them onto the stack and a line goes only when three of them match on all three counts — about one random triple in twenty-seven. Arranging the rest is the game.
THREE DEPTHS
Harbour is a tutorial rather than a level: colour only, thirty pops, long enough to learn the shape of it.
Ocean is the game played straight — colour, number and shape together. 3.7% of triples clear.
Deep adds a facing arrow and a wider board. 1.6%.
ONE BOARD A DAY
The daily is the same puzzle for everyone on Earth, and you get one attempt at it. Not one attempt unless you pay: one attempt. Finish it and you see where you landed among that day's players.
SCORING FOLLOWS RARITY
A hundred a piece, plus a bonus for how much the line has in common. Orders that read 1-2-3 pay double. Read them 3-2-1 and they pay triple.
WHAT IS NOT IN IT
No ads. No in-app purchases. No unlocks, no tiers, no energy, no timers, no account, no sign-in, no newsletter. Stackit is bought once and that is the end of it.
It plays with no connection at all. The only thing that ever leaves your phone is a daily score, and only when you finish one — never your name, which stays on the device.
Eight rule shapes. A hundred and forty-four trios that clear. Three sweeps a match, for when the stack gets away from you.
Three pieces that agree on everything clear the line. No ads, nothing to buy.