First Game:
- All players gather in a ring and put both their fists out.
- One person starts by saying a phrase (which varies depending on what part of the country you come from, basically the phrase itself doesn't matter, it's just to signify you're about to say the number) followed by a number.
- The moment that person says his/her number, everyone in the group independently has the option of doing nothing, raising their left thumb, raising their right thumb, or raising both their thumbs. This is done in an instant; in other words, some random number of thumbs will collectively be raised at the same time the person says his/her number.
- Afterwards, the number of thumbs sticking up is counted. If the count doesn't match the number said, nothing happens and no fists are removed from the ring. If the count does match the number said, those fists that have their thumbs sticking up are removed from the ring. It doesn't matter whose fist it is.
- The remaining fists go for another round and another person does the phrase & number call. This repeats.
The goal of the game is to get both your fists out of the ring. The strategy is such that you want to try and predict what number the person will say, as well as how many thumbs will be raised by the others still in the ring, so that you can try and match those numbers by raising at least one of your thumbs so you can pull a fist out. If you successfully do so you "survive" the round.
Yes, you're technically at a tactical disadvantage when you decide to not raise any thumbs, since if the thumb count is correct you won't be able to take any of your own fists out of the ring, but that's only if the count matches up. Leaving one or both of your thumbs down can mess with the thumb count as well if the person calling assumes everyone will put their thumb up. If you get into a situation with all the remaining players only have fist in the game though, you're technically at a stalemate, since the best strategy at that point is to always raise your thumb no matter the call.
Once you get down to two players left, you can consider them the "losers" of the match and start over. You can end up with one "loser" though if everyone except one person guesses the number right.
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Second Game:
This is just a variation of some other group counting games, it's not a strictly "Japanese" game per se.
- The goal is to say a number that collectively counts your group from 1 to the number of participants in the game minus one (e.g. seven participants, count from 1 to 6).
- You cannot say the same number as another participant(s) at the same time. If you do, the round ends and you and everyone else who said that number at the same time "lose" that round.
- You also lose if you say the wrong number in the order (aka. if you can't count and say a different number or something else entirely).
- If you end up as the last person remaining who didn't say a number, then you're also the "loser" of that round. (although at that point, if you get down to two people remaining the game just becomes a contest of speed and best strategy generally means both players will lose if they're paying attention)
In order words, in order to "survive" the round, you want to try and say a number as soon as possible without saying it at the same time as another player in the group. If you do so, you're considered a winner and can just spectate the rest of the round. In the 4-koma, the comedy is that everyone wants Komi to lose so that they can see her make a kissy-face, so they become so focused on winning that they all just shout "1" (in addition to one guy screwing up) at the same time and instantly lose.