Sumo Shove

Everyone starts spread round a sandstone disc over a pit, facing the middle, with nothing at the edge to stop a fall. The rim drops away a ring at a time, and by the end of a heat whoever is left shares a patch of stone 6 metres across. Few falls come from one big hit. Most are a push that leaves someone at the lip, then a second push before they have walked back.

Three heats on a crumbling disc

A round is three heats of up to 60 seconds, each on a fresh disc, and your finishes are added together. One early fall costs you a heat, not the round.

At 0:19 the outer ring glows red, and a second later it drops. Another follows every few seconds, paced so the last goes at about 0:50 whatever the size: every 7.5 seconds on the 16-metre disc two players get, every 2.5 seconds on the 32-metre disc for sixteen. If more than one of you is standing at the buzzer, whoever landed more hits places higher, so hiding in the middle does not tie a heat.

Two events land in each heat, around 0:20 and 0:42, after a five-second countdown. A Sandstorm pushes everyone one way for four seconds, along the line of blinking markers, at about half walking speed: keep walking into it. Pillar rises puts a stone pillar in the middle for 8 seconds, shoving out anyone standing there. Crumble drops the next two rings at once.

The four skills

• Q Shove knocks everyone within about 2 metres, in a wide cone in front of you, about 2 metres back. Hold it up to 0.8 seconds and it lands nearly twice as hard, but you crouch and walk at half speed while winding up, so everyone sees it coming. Ready 1.2 seconds after you let go.
• E Shield is a bubble for 0.7 seconds, every 5 seconds. A fireball that hits it flies back as yours, a blast does nothing to you, and shoves and dashes land at a third of their strength.
• R Fireball flies flat and fast, bursting on the first person, floor or solid thing it meets and throwing everyone within 2.8 metres. A direct hit also roots the target for most of a second. One every 5 seconds.
• F Dash lunges about 2.6 metres the way you face, every 4 seconds, and knocks anyone you pass close to along its line, harder than a tapped shove. Nothing stops you dashing off the edge.

Rules a heat can roll

Most heats announce a mutator. Big shove makes shoves and dashes hit half as hard again. Small world starts three rings smaller and crumbles from 0:10. Sky-high throws people up as well as back. The Sphinx's gaze sweeps a golden beam round from the middle like a clock hand, one lap every 12 seconds, flinging outward anyone it touches. Quake drops a random ring anywhere but the very middle every five seconds from 0:08, filling the disc with holes.

How good players win

• Keep your back to the middle. Every hit pushes away from whoever lands it, so the player nearer the rim is the one in danger. Circle until it is them.
• Know what the final disc takes. From its middle, one full wind-up or two taps from the same side put someone off. Taps keep you moving; a wind-up halves your speed and shows.
• Shield on the throw, not before: the bubble only lasts 0.7 seconds. A parried fireball counts as your hit.
• Dash sideways out of a fireball's line, or straight at someone standing just out of shove reach at the rim.
• Step in the moment the outer ring turns red. One second is less time than it sounds.

After you fall

You come back as a ghost, and your Q becomes a gust about half as strong as a shove, every 8 seconds. It will not move anyone from the middle, but it tips a player already at the lip.

The host can also switch on Rewind, which gives everyone G: hold it to slip back along your own recent path, even mid-fall, while a 3-second sand bar lasts.