Stack

How to play

A white block slides left and right above your tower. Tap, click or press space to drop it. Only the part that overlaps the block below survives. The overhang falls away, and the next block is that same narrower width.

So the game punishes imprecision permanently. A tap that is 20 pixels off does not cost you 20 pixels once, it costs you 20 pixels on every block after it. The game ends when the surviving width drops below about ten pixels, or when you miss entirely.

Land within three pixels of perfect and you get the full width back, which is the only way to recover lost ground. That is what the Perfect counter tracks.

Strategy, such as it is

Do not aim at the block. Aim at where it will be.

There is a delay between deciding to tap and the tap registering: your own reaction time plus your device's input latency, together often 200 to 300 milliseconds. At the speeds this game reaches, the block travels a visible distance in that window.

Which means aiming at the aligned position guarantees you are late. Release slightly before it looks right. Most players never work this out and never understand why they are consistently off in the same direction.

Use the turnaround

The block is momentarily slowest in appearance at each end of its travel, because it reverses there. If your tower has drifted towards one side, the edge nearest that side is the easier place to time a drop. Experienced players deliberately let the tower drift towards an edge for this reason.

Chase perfects early, not late

A perfect at width 200 preserves 200 pixels. A perfect at width 40 preserves 40. Early precision is worth several times what late precision is worth, which is the reverse of how most players approach it, relaxing at the start and concentrating once it gets tight. By then the tower is already narrow and there is little left to protect.

Why this design works

Stack is a good example of a mechanic where difficulty is generated by the player rather than the designer. Nothing in the game gets harder on a schedule. The speed increases slightly, but the real difficulty comes from your own accumulated errors, each of which narrows the target for every future attempt.

This produces a distinctive feeling. Losing never seems arbitrary, because you can point to the exact tap that started the decline. That is also why it is hard to stop playing. Every failure comes with an obvious lesson, and an obvious lesson is an invitation to try again.

The contrast with a game like Snake is instructive. Snake gets faster by design and its difficulty is imposed. Stack narrows because of you, and its difficulty is earned.

What counts as a good height

Height	Roughly
Under 10	Still learning the timing
10 to 20	Comfortable with the rhythm
20 to 35	Compensating for latency, probably without noticing
Above 35	Deliberately hunting perfects

Your best height is stored in your browser on your own device and never uploaded.

Common questions