The water in the lock chamber is always rising or falling. Tap to reverse it, and hold it inside a waiting barge's band until the barge floats through. Two queues wait, upper and lower; a fifth barge in either one overflows the canal.
👆 Tap anywhere to switch between flood and drain ← All gamesLockgate puts you in charge of a busy canal lock at night. The water in the stone chamber never stands still: the sluices are always either flooding it or draining it, and the only thing you control is which way it runs. Tap anywhere to reverse the flow. Barges wait in two lines, one on the raised upper pound to the left and one on the lower pound to the right. The boat at the front of each line needs the chamber held at its own draft mark, shown as a coloured band on the gauge and on the chamber wall, and it floats through once the water has stayed inside that band for long enough. A ring above each boat fills up as it takes on water.
New barges glide in from the edge of the board and join a line every couple of seconds, and the lamps along the towpath count each line up to four. If a fifth barge arrives at a full line, the canal backs up and the shift ends. A band slips past in under a second, so you will tap back and forth to hold the water inside it. Deep barges have narrow gold bands near the top of the chamber and need a long fill. They pay double, but while you hold the water for one, the other line keeps growing. Which band to visit next, and in what order, is the whole game. Clearing barges within four seconds of each other builds a multiplier up to six times. A gap, a full line or a grounding resets it.
At 25 points a bar of silt starts drifting up and down the chamber. You can sweep straight through it, but reversing inside it or lingering there grounds the lock. That breaks your multiplier and sends an extra barge to the busier line. From then on, the route to each band matters as much as the band itself.