Leave a ball on a quiet pavement. Players take bets on whether each passer-by will kick it.

Take a glass of orange juice. Add a tsp. of salt each turn. Sip. First to spit out drink loses.

Back in 2013, an awful lot of people on Twitter made up games designed to fit in a single tweet. They shared them using the hashtag #128CharGames, in a project initiated by game designer and conceptual artist Zach Gage. Gage wrote up the results of his experiment here – dozens and dozens of minimal games and ideas, all folded down into just a sentence or two.

The project itself was pretty great, and so were a lot of the games that people designed. So as part of Now Play This, our September event at Somerset House, we got permission from Gage and the designers of our favourite contributions to print up their games on index cards and show as part of an exhibit of instructional games and artworks. And then we left a little pile of index cards on a table, thinking that a few people might want to add their own.

Well, gosh, they definitely did. By the end of the weekend, a trail of 128-character games had stretched out across the whole wall, jumped across a doorway to another wall, and then turned the corner to yet another wall, encircling half the room. (You can look through the gallery above to get a sense of how it all progressed.)

It’s taken us a few weeks to sit down and go through all the cards, but finally: here are the games that visitors added over the course of the weekend. People didn’t leave their names, for the most part; just an amazing array of spur-of-the-moment games and ideas and fragments and playable jokes. We’ve made a couple of minor copyedits – and we’re pretty sure a few of the games went missing at some point, perhaps grabbed by really zealous players who wanted to try them out? – but the rules are otherwise unchanged. Thanks so much to everyone who added a game to the wall, and to the designers of the games from the original 2013 experiment for letting us show their work.

Throw a grape through a tennis racquet without breaking.

Find 127 people whose name doesn’t share any characters with yours.

Make a girl fall in love and never call her again.

Exchange pictures of ceilings you are currently under. Try to guess where others are.

2+ players. 1 player closes their eyes and other players make guesses at that person’s eye colour. 1 point per correct guess.

Watch the movie “The Room”. First one to laugh loses.

Row of pints. 2 players. Down pints. First to burp loses.

Blindfolded friends have 30 secs to pick up objects from the room. You guess them by rubbing them against your face.

Blindfolded person. Have to guess sock or cheese.

Whoever makes a decent gluten-free loaf wins.

First person to make themselves sneeze wins.

All players bite their thumbs. Whoever’s bite mark lasts longest wins.

Insert egg-based puns into casual conversation. Last standing wins. Play continues indefinitely.

You and another player take turns to tell each other “I love you”, first to laugh, smile or otherwise stop loses.

Two players: first must leave Somerset House by any exit, without the second player following them out within ten seconds.

pram = cart: gain 10 points. Umbrella/phone = wizard: lose 10. 1 metre effect radius. Go walk, start on 20 points. Don’t die.

One person thinks of a cheese and declares “I’m thinking of a cheese”. First person to guess correct cheese wins.

Everyone says a sentence – the first thing that comes to mind. Write it down. Closest to 128 characters wins!

Visit a friend with a pet. See how long you can last without touching it.

Don’t let them catch you.

Try and jump a fence or climb a tree with super tight trousers. Player whose trousers rip first loses. Oops!

Draw a world/scene and then explore the world/scene (make stuff out of pillows and objects)

Turn half the lights on in your home. One person switches them on, other off, to music. When music stops, count lights on/off.

Get donut. Get marble. Throw donut up. Throw marble through donut. Do not eat marble.

Walk 20 paces in one direction. Close eyes, turn around, walk 20 paces back with eyes shut. Win if you end where you started.

One player is “target”: other players heap merciless praise on target, who has to deflect/deny everything modestly. Variant: merciless insults.

Literary superlatives. Name something: greener than my valley, higher than heaven, etc.

Steal an egg. Then steal a car. Then steal money in a bank. Go in jail. Escape. You win.

Exchange only 4 letters in an existing word to create a new word. 4 letters can be added or subtracted, or a mixture of the two.

Buy fruit. Hand it out to strangers. Keep going until someone refuses your fruit. Last person still playing wins!

Create random tinder account. Each swipe yes/no as many times in 1 minute and see who gets most responses.

Imitate mating calls of different beasts. First successful copulation wins. Or maybe loses.

Go to IKEA. Built a fort from the furniture. Hold out as long as you can. Last one in the store wins.

Describe an actor as vaguely as possible: hair style, obscure advert they were in, costars. Winner becomes the describer (“Mum”).

Each player has a packet of smarties. Choose a colour. Highest number wins! (Then you can scoff them all.)

Step 1: eat fibre. Step 2: go to toilets with friend. Step 3: Biggest poo wins.

Car wheels fire lasers sideways, stationary cars block lasers, get down street safely.

Take a glass of orange juice. Add a tsp. of salt each turn. Sip. First to spit out drink loses.

Run a sentence through 3 languages in google translate and then back to English. Friend guesses original phrase.

Call random 0800 number, ask for free stuff. Give name as Matt Crab Barnes. Each level, insert extra crabs. Player who gets stuff in post with most crabs wins. [technically this is way over the character limit, but it’s also great]

Leave a ball on a quiet pavement. Players take bets on whether each passer-by will kick it.

Stand on one leg and throw an egg in the air. Points = catches before it breaks.

Take these flyers. Write your number. Hand out on Strand. First call or text wins. 2+ players.

Try not to die.