Monday, September 21, 2015

Time Bomb, a simple and excellent card game of suspicion

Today, I attended a Mensans' local meeting. In this visit, we enjoyed some card games.

Mensa is an association whose members are gifted. To belong to Mensa you have to pass an examination to prove his or her intelligence level is extraordinarily high. In spite of the image from this description, Mensans' meeting is quite cheerful and sometimes crazy.

My past entry: Mensa and the goal of life

Today, I played some games: Dragon's Gold, Texas Hold'em, Cockroach poker, and so on. Among them, I was impressed by "Time Bomb."

Time Bomb is a card game created by Yusuke Sato, who is a Mensan. It has quite simple rules, but is very attractive. We were so fascinated by it that we played it several times successively. I will introduce the core rule of this game.

Koenji zero-minute Sugorokuya: Time Bomb (in Japanese)

When there are six players, four players play a role of SWAT, and the other two players are terrorists. Which role you will play is determined by the card delivered to you. You cannot show your role card to any other players.

Each player are given five fuse cards. In the six-players game, there are six "Success" cards, one "Bomb" cards, and other twenty-three "Safe" cards. You can see the component you were given, but showing them to other players is not permitted.

The game starts with the first player's challenge. The first player has to choose one other player to open one fuse card he holds. If the "Bomb" card is opened, the game will end immediately with the victory of the terrorists. Otherwise, the player whose card was opened will be the second player to challenge the choice.

When a total of six opening is completed, the first round is finished. Any fuse cards which have not been opened are returned to be shuffled. All opened cards are discarded. The second turn will start after delivering all remained fuse cards (Each player will be given four fuse cards). The first player is the last player whose fuse card was opened in the previous round.

The game will end by the victory of SWAT in the case all six "Success" cards is opened. Otherwise, the terrorists will win when the fourth round ends.

That's all, extremely simple.

In this game, the SWAT players have to find all "Success" cards. Therefore, they have to exchange the information about the components of the fuse card each player hold. For example, one player can declare "I have two Success and three Safe." If his saying is reliable, it is reasonable to open his card because you have 40% opportunity to open a "Success" card without the risk of hitting the "Bomb" card. However, if he is actually a terrorist holding the "Bomb" card? You can ask other players about the contents of the fuse cards they hold. The total number of "Success" cards is fixed. If he is lying, the total number would be paradoxical. However, you have to remember that there are two terrorists. They can support each other with lying consistently. Confused?

Usually, SWAT players are honest and the terrorists are liars. Consider this case. If you are a SWAT with the "Bomb" card, you will say the truth, to prevent other SWAT players from opening your "Bomb." OK? However, if you declares so, it helps the terrorists to open your "Bomb" card! It is often wise to make a lie to deceive not only opponents but also allies, especially about the existence of the "Bomb" card.

There are many other situations you can choose the tactics. It is quite a cool and sophisticated game. I would like to play it again.



  1. I live in Portugal and I would love to buy the original version of Yusuke Sato's TimeBomb. Where can I order it? Please contact me at Thanks in advance! Flavio.

    1. Sugorokuya at Koenji in Tokyo, a famous analog game shop, deals with Time Bomb. But international shipping seems not available there. Sorry that I cannot support you about this.