How to Master Coast
TLDR: A stone launches along a track and slows to a stop in one of several numbered zones. Tap the zone before it settles. Call it early for a faster reaction time but higher risk; wait until it nearly stops for certainty but a slow time - and if you wait too long it stops before you commit and the run ends. Each correct round launches the stone faster, tightening your window.
How the Game Works
Coast has one mechanic: a stone launches along a track and decelerates under friction until it stops in a numbered zone. Tap the zone you think it will land in before it settles. Call correctly and you advance to the next round, which launches the stone faster. Call the wrong zone, or let the stone stop before you tap, and the run ends.
Your fastest correct call - measured in milliseconds from launch to tap - is saved as your personal best. That’s the number to chase.
The game is deterministic. Every round’s launch speed, friction, and final stop position come from a seed, so the same setup always plays out identically. The board never changes size: each successful round just increases the launch speed, tightening your decision window. The further you get, the faster you must commit.
The tension is built into the design: Early calls score faster times but carry more uncertainty - a fast-moving stone is hard to extrapolate accurately. Late calls are easy to read but slow to score, and if you wait too long the stone stops before you tap and the run ends. There is no neutral option.
Reading the Stone’s Trajectory
The core skill is visual extrapolation: given where the stone is now and how fast it’s moving, predict where it will stop. This is trainable.
Watch the stone’s deceleration rate closely during your first few attempts at each speed level. The rate at which it slows is fixed for that round - the deceleration is constant for a given launch speed. A fast launch shows a steeper initial deceleration; a slower launch coasts more gently. Learning to distinguish these curves gives you useful predictive information early in the stone’s journey, before most of the deceleration has happened.
Track two things simultaneously: current position and current velocity. A stone at position 4 moving quickly has a very different destination than a stone at position 4 barely crawling. Both inputs together - not either one alone - tell you where the stone is going.
Zone elimination by momentum: As the stone coasts, actively narrow which zones it can still reach at its current speed. Early in the journey, many zones are viable. As it decelerates, the reachable set contracts quickly. Watching this contraction lets you eliminate outer zones before they’re obviously ruled out, reducing your decision from “which of five zones?” to “which of two?”
The Speed-Accuracy Tradeoff
Coast puts a fundamental tradeoff at the center of every round: calling early is fast but risky; calling late is safe but slow and ultimately fails when the stone settles first.
Early calls occur when the stone is still moving fast. Small errors in your position estimate turn into large zone errors. A stone at half its initial speed might still travel two zones further than you think. If you’re correct, though, your reaction time is excellent - potentially under 500 milliseconds on later rounds.
Late calls occur as the stone nearly stops. The correct zone is almost obvious, but your reaction time is slow - potentially over 1,000 milliseconds. And if you wait just slightly too long, the stone stops before you tap. The run ends on the same hesitation that was supposed to ensure accuracy.
Finding your balance point is the main skill progress. A good starting target is roughly 70-80% call accuracy with moderate times. As your trajectory-reading improves, push that commitment point earlier while maintaining accuracy.
The consistent commitment point: Pick a moment in each stone’s journey - when it crosses a visual midpoint, or when it reaches a particular speed you can recognize - and practice committing at that moment consistently. This trains a repeatable process rather than ad hoc judgment, which is easier to improve deliberately.
Warm-up rounds to calibrate: Start each session with two or three conservative, late calls. These establish your visual calibration for the current speed level and build the streak foundation. Once you’ve won a few rounds and your eye is tuned, shift your commitment point earlier. Skipping calibration rounds leads to early misses from uncalibrated instincts.
Common Mistakes
Calling too late then panicking. Players who wait for certainty find themselves with barely any time left and tap reflexively - often missing even though they saw the right zone. Accepting moderate risk and calling slightly earlier is less stressful and leads to better outcomes.
Rigid strategy across speed levels. A calling point that works at round 3 often fails by round 10, when the stone is launching much faster. What feels like the right moment to commit shifts as launch speed increases. Expect to recalibrate your commitment point as you progress through a streak.
Uninformed fast calls. On fast rounds, some players tap immediately just to post a quick time. Random zone selection at high speed fails far more often than it succeeds. Fast calls still need to be informed calls - take a fraction of a second to actually read the stone’s trajectory before committing.
The stone stops before you tap: If you let the stone fully settle before committing, the run ends even if you tap the correct zone a split second later. Accept some uncertainty and commit while the stone still has momentum. A correct early call is always better than a correct late non-call.
Accuracy beats time: A correct call in 1,200 milliseconds advances you. A wrong call in 300 milliseconds ends your run. Never sacrifice correctness for speed. When genuinely uncertain, wait slightly longer - a slow correct call is better than a fast wrong one.
Practice Structure
Week 1 - Build familiarity: Focus purely on winning rounds. Don’t chase reaction time yet. Get comfortable with the deceleration pattern and find a consistent late-ish calling point. Build a streak of 5+ before caring about time.
Week 2 - Note your times: Start tracking your personal best. Compare times across sessions. Find the pattern: when are you calling fastest? What trajectory cues are you using at that moment?
Week 3 - Push the commitment point earlier: Deliberately try to call half a second earlier than your current habit. Accept that accuracy may drop slightly. When it drops too far, pull back slightly. This deliberate calibration is how the commitment point improves.
Post-round reflection: After each round, assess: was that call too conservative, too aggressive, or well-calibrated? Did the stone stop where you predicted? The ten seconds of reflection after each round compounds into faster learning than just playing more rounds mindlessly.
Advanced Technique
Pre-launch zone ranking: Before the stone launches, use context from previous rounds at this speed to mentally rank which zones are most likely. A fast launch on this board tends to reach zones 4-6. Narrowing the set before the stone moves means you’re answering “zone 4 or 5?” rather than “which of seven?”
Deceleration curve sensing: Different rounds have different launch speeds, which means different deceleration profiles. A very fast launch decelerates more steeply early; a moderate launch decelerates more gradually. Learning to feel these profiles - even just “this feels fast vs. normal” - gives you extra predictive information in the first half of the stone’s journey.
Use your personal best as a guide: Coast saves your fastest correct call in milliseconds. Each session, your goal is to either match or beat that number at least once. Concrete targets - shave 50 milliseconds off last session’s best - convert a fuzzy “get better” aim into a specific, measurable challenge.
How Progress Feels Over Time
In the first few sessions, zone identification happens consciously - you watch the stone, estimate mentally, then tap. With practice, the process telescopes: by round 5 of a good session your eye is reading velocity and position simultaneously without deliberate effort, and the right zone often “presents itself” before you’ve reasoned through it explicitly. That shift from calculation to perception is what the game is actually training.
The speed increase per round is gradual enough that you rarely notice the difficulty tightening in real time. The signal is when a call that felt comfortable at round 3 suddenly feels rushed at round 8. When that happens, it’s not a slump - it’s the game working. You’ve reached the edge of your current calibration. A slight pull-back in commitment timing, two or three rounds to re-establish the deceleration curve read, and the comfort returns at the new speed.
Track your pattern across sessions: Do you consistently miss the same zones? Overshoot on fast launches, undershoot on slow ones? These patterns reveal the specific part of your mental model that needs recalibration. They’re more informative than raw streak length.
Your personal best is always waiting to be beaten. Whether your fastest call is 900 milliseconds or 400, the path is the same: read the stone’s trajectory earlier and earlier, calibrate your confidence, and commit while the stone still has room to run.
Coast
A stone coasts to a stop · call the zone it lands in before it settles. Call it early while it is still fast to chase a faster reaction time
Play nowWorks on any device.
