Gridlock

Gridlock puts you in charge of one junction with no traffic lights except you. Four lanes feed a single shared box, a car rolls up each lane toward the stop line, and only the lane you have given right of way to is allowed in. That is the entire rule set, and it is plenty. A car that gets the green while another vehicle is still in the box causes a crash; a car left waiting at the line too long — about six and a half seconds — runs out of patience and ends the run just as surely. So you are juggling two opposite failures at once: switch too eagerly and you cause a collision, hold a lane too long and someone else times out. Cars arrive at different speeds, so the queue you are looking at is never quite the order they will reach the line. Each car that crosses scores a point, and every five points the gap between new arrivals shrinks, so the quiet early stretches disappear. Beginners stare at the lane they just opened; good players keep half an eye on all four stop lines, watch for the wait meter turning amber, and change the light just as the box clears. Arrow keys, WASD or a tap on each approach all work.