Trail Duel Strategy: Winning Space Against the Computer Rider

Updated October 2026

Trail Duel is a duel of territory. You and a computer rider move one square at a time across a walled grid, each leaving a solid wall behind, and the first one with nowhere to go loses. Because both riders move at the same moment and at the same pace, raw speed never decides a round. What decides it is space: who controls more of the board, and who notices first that the other has run out. This guide explains how the arena, the turning controls and the computer opponent actually work, so you can plan rounds instead of surviving them.

The arena and the clock

The board is 22 squares wide and 34 tall, 748 squares in total. You start near the lower left, in the fifth column from the left and the sixth row from the bottom, heading up. The computer starts at the mirror-image point near the upper right, heading down. Every square either rider has visited stays filled for the rest of the round, and entering a filled square or leaving the board ends that rider's round.

Movement happens in ticks. Both riders choose a direction, then both step at once. In round 1 a tick lasts 140 milliseconds, about seven squares per second. Each round you win shortens the tick by 8 milliseconds until it reaches 70 milliseconds in round 10, roughly fourteen squares per second, and from there the pace stays the same. The pace is always shared: the computer is never faster than you. Because the speed is measured in squares rather than pixels, a small phone and a large tablet play exactly the same game; only the drawing gets bigger.

From round 4 the board is no longer empty. Short grey wall segments appear, eight more squares of them every round you reach, up to two fifths of the board. They are placed as a mirror image through the centre, so the computer's side always has exactly the same obstacles as yours, and the area around both starting points and the first few squares ahead of each rider are always kept clear. A grey square is as deadly as any trail.

The round waits on the opening screen until you first touch the board or press an arrow key, and the clock is tied to the screen's animation, so switching to another app pauses the duel rather than letting it run without you; at most a step or two plays out when you come back.

Turning: what a tap really does

On a touch screen there are only two commands. A touch on the left half of the board turns you a quarter turn to your own left, and a touch on the right half turns you a quarter turn to your right, measured from the direction you are travelling now. When you are heading down the screen, "your left" is the screen's right, which is the single most common source of crashes for new players.

Turns are queued and applied one per tick, and each new turn is worked out from the last turn already in the queue. Two quick taps therefore both count: two lefts make a tight U-shape over two steps, and a left followed by a right makes a one-square jog. The queue holds at most two turns, so extra taps beyond that are ignored. A reversal is impossible in any case.

The first touch of a round only starts it; you keep running straight until you tap again. On a keyboard the arrows set an absolute direction, up, down, left or right, which many players find easier in the later, faster rounds.

How the computer thinks

Knowing the opponent's decision rule is the biggest advantage you can have. It changes as the rounds go by, and it keeps getting stronger.

• Round 1: the computer only avoids squares that would crash it on the very next step, and otherwise picks among them almost at random. It routinely boxes itself in.
• Rounds 2 to 4: for each safe direction it counts how many open squares it could still reach from there and chooses the largest. The count stops at a horizon of 120 squares in round 2 and the horizon grows by 40 squares every round. It prefers to keep going straight when the counts are close.
• Rounds 3 and 4: it also adds a small bonus for directions that bring it closer to a point three squares ahead of you along your current heading, so it starts steering to cut across your path.
• From round 5: it stops chasing and plays for territory. For each safe direction it works out which open squares it would reach before you and which you would reach first, and picks the direction that leaves it the bigger share, while steering clear of small dead-end pockets. It also makes deliberate mistakes, a random safe move about 30 percent of the time in round 5, and that rate shrinks by 15 percent every round, so it gets steadily harder to beat.

In every round from 2 on it also refuses to step into a square that your head could enter on the next step, unless no other move is safe. Charging straight at it therefore almost never forces a head-on crash; it simply swerves.

The early horizon is still a blind spot worth using: in round 2 a region of 121 squares looks exactly as good as one of 500 to the computer, so when the board splits it may choose the smaller side. From round 5 that weakness is gone, and you have to win the territory battle honestly.

Winning rounds: territory first

Every round eventually becomes a race to fill space. Once your walls and the computer's walls separate the board into two regions, nothing either rider does can affect the other, and whoever has more room will outlast the other. Your job before that moment is to make sure the dividing line leaves you the bigger side.

• Claim the middle early. Your starting heading takes you up the left side. A turn toward the centre within the first few steps lets your wall start dividing the board rather than hugging the edge.
• Build long walls, not tight curls, in the opening. A long straight line splits the board in a way a curl cannot. Tight packing is for the endgame, once you are sealed in.
• Close the door, then count. When the computer is on the far side of your wall, look for the gap it could use to reach your side and seal it. Then estimate both regions. If yours is larger, simply fill it carefully.
• Fill your region in rows. Moving back and forth in lanes, like mowing a lawn, keeps the unused part of your region in one piece. Wandering turns tend to split it into small pockets you can never come back to.

Dealing with a chasing opponent

In rounds 3 and 4 the computer is drawn toward the space just ahead of you. That makes it more dangerous in open space, but it also makes it predictable: when the counts are close, it bends toward your path. Lead it along a wall it is already near, then turn away. Its pull can carry it into a corridor that is too narrow to turn around in.

A collision where both riders crash on the same tick, including meeting head-on in the same square, is a tie. The board resets (with a fresh set of grey blocks from round 4), the round number stays the same and no points are added. Because the computer avoids squares you could enter next, ties are now uncommon. In our simulation, where a simple bot that always picked the largest open area, with an occasional random turn, played against the computer, about 9 percent of round-2 duels and only 1 to 3 percent of later ones were ties, while round 1 was won about nine times in ten.

A tie is still better than a loss, but you cannot count on the computer to collide with you. When both riders are converging on the same square, it will swerve; make sure the swerve does not leave you the smaller region.

Scoring and how runs end

Each round you win adds 10 points and moves you to the next round. A loss ends the run immediately, and the result card offers to save any score above zero to the Hall of Fame. Your best is kept on this device.

The pace stops rising at round 10, but the computer keeps making fewer mistakes and the grey blocks keep multiplying, so the challenge never levels off and every run ends. In our simulation even a strong territory bot, one that judged the whole board perfectly every step and never mistimed a turn, lost a median of 8 rounds in and never got past round 19. A long run is about clean decisions at fourteen squares per second: decide the next turn while you are still travelling in a straight line, and use the double tap only when you mean a U-turn.

Quick checklist

1. Remember that left and right are relative to your rider, not to the screen.
2. Two quick taps queue two turns, one per step: use them for a tight U-turn or a one-square jog.
3. Divide the board early with a long wall that gives you the larger side.
4. Treat grey blocks as free walls; the computer's side has the same pattern as yours.
5. Fill your own area in lanes, and leave the computer to run out of room.