Your archer paces the wall. Each chevron in a lane carries the arrow one tick on the wall. Count them, and tap when you stand that far off the brass mark.
Tap the field, click or press Space to loose. One miss ends the run; if the count runs out, the archer looses wherever they stand.
The brass mark on the wall is level with the target (with a sliding target, with where it will be when your arrow arrives). Brass chevrons blow up the screen, steel ones down; each one carries the arrow one tick (3 m). The centre is gold; a miss is called left or right as the archer faces, so left is up the screen. Later on: more lanes, winds that cross, gusts that flip (watch the red fuse) and a target that slides.