The flick

Press your cap, drag backward and let go. The further back you pull, the harder it goes.

Playing a friend, you can see the line they are taking while they aim, but never how hard they are about to hit it. That much stays theirs.

The fan shows roughly which way the cap is headed. The power meter at the top of the screen shows how hard you are hitting it, where your thumb cannot cover it, and on a phone you will feel a small notch every quarter of the way up. How far the cap actually runs is down to you, not the game.

A cap sitting near the edge is not weaker. When there is less screen to drag into, less of a drag counts as a full pull.

If a cap is awkward to pull back from, walk around the court. The rocker in the bottom left carries you round to any side, so you can always put the cap between you and the middle and give yourself the whole screen to drag into. Tap it to come back to where you started.

On a keyboard: [ and ] to walk around, 0 to reset. It is only where you are standing. The board, the caps and whose turn it is do not move at all, and the chalk stays chalked to the ground, so from the far side the numbers read upside down just like they would in the street.

Friction does the rest. Caps knock each other around on contact.

The run

1. Everybody lines up in the START box, off the court past box 1, and has to shoot their way in.
2. The run is 1 up to 13, then 13 back down to 1. Only then are you a killer.
3. The numbers do not run around the court, they zigzag. 1 and 2 are opposite corners, 3 and 4 the other two, then the side pairs, then the pairs top and bottom, then 13 in the middle.
4. The cap must sit fully inside the box. Touching the chalk does not count.
5. Land your box and you shoot again. Miss and the turn passes.
6. You have twelve seconds to take a shot. Run the clock down and the turn passes.
7. Clip another cap with your flick and you are walked into the box you were chasing, and it counts.
8. Knock another cap into the box you were chasing and you skip two.
9. A clean box also buys you a set up: slide your cap anywhere inside that box before your extra shot, so you can line up the run to the next number.
10. Off the board means the turn ends and your cap is set back on the edge where it left.

The skull

The square in the middle is the skull, cut into four K zones that point at box 13. Stop in one and you are dead for a turn: you sit the next one out.

13 is the safe island in the centre, so the only way through the skull is a clean landing.

Killer

Ride 1 up to 13 and all the way back down to 1 and you become a killer. No more boxes to chase. Now you hunt: touch another cap with yours and that player is out.

Killers are not safe either. Stop in the skull zone as a killer and you lose the status, back to chasing 13.

Last cap on the board wins.