A dot slides along a wire. Tapping flips its gravity to the wire's other side. That's the whole rulebook — everything else is what the wire does to you. Wires curve, spiral and split; spikes wait with just enough warning to dodge them, if your timing's honest; gaps open under the wire and the dot has to cross on nothing but physics.
Every hazard is deterministic. There is no randomness anywhere in the simulation, which means no death is ever unfair and every death is repeatable. That's the whole point: you should be able to feel that it was yours.
One touch and it's over. Restart is instant — no loading screen, no "tap to retry," nothing between the death and the next attempt but the death itself.
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Tap anywhere and gravity flips the dot to the wire's other side. That is the entire control scheme. -
Wires curve, spiral and split, and where they split the dot takes the prong on the side of the wire it is on. -
Spikes arrive with just enough warning to flip past them — if your timing is honest. -
Identical taps produce identical results, on every device, every time. Nothing is generated and nothing is rolled. -
Hand-built levels, each carrying the count of what it has cost you so far. -
Instant restart, and a running total of every death it has taken to get this far.
70+ of the hardest levels, hand-built
Kerfline ships with 70+ hand-built levels, not generated ones, ramping in difficulty honestly across the whole ladder — the later traps of spikes, gaps and spiraling wire are genuinely hard. Each level tracks your deaths and shows the share of players worldwide who've actually finished it — usually a humbling number. A per-level timer clocks your best runs, but the global leaderboard ranks fewest deaths, not fastest time, because two players on the same route tie on time and only one of them died less. Clear a level and share your result in one tap. No wifi needed — every level plays fully offline.
Cosmetics, never shortcuts
Trails and skins are cosmetic only. Nothing you unlock or earn ever makes a level easier, or a spike slower, or a gap narrower. Every one of them is earned by playing well — clearing the hardest levels, finishing one without a single death, or clearing the whole set — so a trail is proof rather than decoration. There is nothing to buy: Kerfline has no in-app purchases.
Ads, handled fairly
Every so often after you die, Kerfline offers an optional ad; turn down several in a row and one is shown anyway. Dying never waits on an ad — the level restarts instantly. You choose what the ads may know about you the first time the game asks, and you can change that choice any time from Settings. If an ad ever misbehaves, you can report it directly — see Support for what to include.
Get it
Kerfline is for iPhone and Android, and it's the same game on both — same levels, same simulation, same leaderboard.