## Yonac |

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Yonac is a quick and easy-to-learn card game developed by Johann Tutor
and Gaetan Boue. Its name is from the Japanese word for “four” and
from the first two letters of “ace”. It is inspired by the game “Ace
of Spades”, described in Bob Phillips’ Super Cool Jokes and Games for Kids.^{1}

Yonac uses a standard deck of cards (Jokers optional). Any number of players may play.

The aim of the game is to collect as many cards as possible without collecting the Ace of Spades.

The four Aces (i.e. the Ace of Spades, the Ace of Hearts, the Ace of Clubs and the Ace of Diamonds) and Jokers are special and are described below. All other cards have no special attributes.

A card is described as “Potent” if its special attribute may be used.

Picking up the Ace of Spades, except when using the Ace of Clubs or the Ace of Hearts, will result in a loss. The Ace of Spades is always Potent.

The Ace of Diamonds forces you to add more cards to the Set. The Ace of Diamonds is Potent on collection and is no longer Potent when it is used to add more cards to the Set.

The Ace of Hearts allows you to pick up the Ace of Spades once without losing. The Ace of Hearts becomes Potent after you collect it and your turn finishes. The usage of this card is described in ¶ 2.2.1.4.

The Ace of Clubs gives you one chance to win instantly. The Ace of Clubs becomes Potent after you collect it and your turn finishes. The usage of this card is described in § 2.2.2.

If Jokers are in play, a Joker will remove Aces from a Set, or if there are no Aces in the Set, you can swap it for another player’s Potent Ace. The usage of this card is described in ¶ 2.2.1.5 and ¶ 2.2.1.6.

The game proceeds in two phases: the Elimination phase and the Sudden Death phase. Before starting, agree on the number of players needed to go into the Sudden Death phase; this is the Threshold. These phases are further discussed in § 2.2.3 and § 2.2.4.

When the Threshold has been decided, shuffle the deck and spread the cards out on the table; this is the Pile. Decide on a player order.

On each turn, you may do one of two actions: you may collect cards, or you may use the Ace of Clubs if you have it set aside.

Each player has a stack of cards, called the Stash, into which collected cards are put. Any cards put into your Stash lose their Potency and may not be used again until the card returns to the Pile.

If you choose to collect cards, pick up one or more cards from the Pile and display them face-up in front of you. These cards are the Set for this turn.

If the Set does not contain any Aces, put the Set into your Stash. Your turn is now over and play proceeds to the next player.

If the Set contains the Ace of Spades and you do not have a Potent Ace of Hearts, you lose and all your cards are reshuffled into the Pile. Play proceeds to the next player.

If the Set contains the Ace of Spades and you have a Potent Ace of Hearts, place the Ace of Hearts in your Stash and reshuffle the Set into the Pile. The Ace of Hearts is now not Potent and it may not be used again until it returns to the Pile. Note that the Ace of Hearts is not Potent if it is in the Set with the Ace of Spades; it must have been collected and set aside in a previous turn for this case to apply. Play proceeds to the next player.

If the Set contains a Joker and there are Aces in the Set, including an Impotent Ace of Diamonds if present, remove the Aces and shuffle them into the Pile. Note that if the Set contains the Ace of Spades, the rules for the Ace of Spades apply instead. Put the rest of the Set, including any Jokers, into your Stash. Your turn is now over and play proceeds to the next player.

If the Set contains a Joker and there are no Aces in the Set, swap the Joker with a Potent Ace of another player if one exists. Remember that Aces in a player’s Stash are not Potent. To perform the swap, place the Joker into the other player’s Stash. Take the Potent Ace and put it into your Set. Do this for every Joker in your Set. If there are no Potent Aces, then you many not perform a swap. After this, the Jokers lose their Potency. Continue to evaluate the Set, including any swapped Aces.

If the Set contains a Potent Ace of Diamonds, pick up one or more cards from the Pile and add them to the Set. Re-evaluate the new Set, with the Ace of Diamonds now no longer Potent.

If the Set contains the Ace of Clubs, put the Ace of Clubs aside; the Ace of Clubs is now Potent. You may play it in a later turn as described in § 2.2.2.

If the Set contains the Ace of Hearts, put the Ace of Hearts aside; the Ace of Hearts is now Potent. It will protect you if you collect the Ace of Spades in a later turn as previously described in ¶ 2.2.1.4.

Put the remaining cards in the Set into your Stash. Your turn is now over and play proceeds to the next player.

If you have a Potent Ace of Clubs, you may choose to play it instead of collecting cards. Once played and put in your Stash, the Ace of Clubs loses its Potency and may not be used again until it is returned to the Pile.

To play the Ace of Clubs, declare that you will be playing the Ace of Clubs. Put the Ace of Clubs in your Stash, then pick up one card from the Pile and display it face-up in front of you.

If the card is not an Ace, put it in your Stash. Your turn is now over and play proceeds to the next player.

If the card is the Ace of Spades, play stops and you win the game.

If the card is a Joker, swap it for another player’s Potent Ace as described in ¶ 2.2.1.6. If no player has a Potent Ace, you may not perform the swap. Evaluate the new card as if that was the card you picked up.

If the card is the Ace of Hearts, put it aside; the Ace of Hearts is now Potent. Your turn is over and play proceeds to the next player.

If the card is the Ace of Diamonds, put it in your Stash and pick up one more card from the Pile. Re-evaluate the new card.

During the Elimination phase, players who pick up the Ace of Spades and lose are eliminated. Play continues until the number of players left reaches the Threshold, at which point the Elimination phase is over and the Sudden Death phase begins.

In the Sudden Death phase, if a player picks up the Ace of Spades and loses, the game ends. The remaining players will count the number of cards in their Stash, including any Aces set aside.

There are two ways to win: by picking up the Ace of Spades while using the Ace of Clubs as described in § 2.2.2, or by not being eliminated and having the most cards your Stash at the end of the Sudden Death phase.

In the event of a tie, the tied player who has the Ace of Hearts wins. If no one has the Ace of Hearts, the tied player with the Ace of Clubs wins. If no one has the Ace of Hearts or the Ace of Clubs, the tied player with the Ace of Diamonds wins. If no one has any Aces, the tied player who had a turn last wins. Note that these Aces do not need to be Potent to count. Also note that if none of the remaining players have had a turn, then the player last in the queue wins.

- Elimination Phase
- (§ 2.2.3)

The first phase. In this phase, the game does not end when a loss occurs. - Pile
- (§ 2.2)

The uncollected cards spread out. In each turn, all cards are taken from the Pile. - Potent
- (§ 2.1)

Describes a card whose special attribute may be used. - Set
- (¶ 2.2.1.1)

The cards picked up during a turn. - Stash
- (§ 2.2.1)

The player’s collected cards. Each player’s Stash is counted at the end of the game. Used Aces are put in the Stash and may not be played again until the Ace is returned to the Pile. - Sudden Death Phase
- (§ 2.2.4)

The second phase. In this phase, the game ends when a loss occurs. - Threshold
- (§ 2.2)

The number of players needed to go into the Sudden Death phase.

This game was inspired by Bob Phillips’ “Ace of Spades”.

The game was suggested by Johann Tutor on July 28, 2016.

The special attributes for the Ace of Hearts and the Ace of Clubs were suggested by Gaetan Boue. The special attribute for the Ace of Diamonds was suggested by Onie Tam.

Joker rules were suggested by Johann Tutor.

The rules were refined and formalized by Johann Tutor and Gaetan Boue.

This document was written by Johann Tutor.

©2016–2018, Johann Tutor.

This work is licensed under the Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/ or send a letter to Creative Commons, PO Box 1866, Mountain View, CA 94042, USA.

This document was typeset with L^{A}T_{E}X. The source code and updates are available on GitHub: https://github.com/jmbtutor/yonac

- 1
- Bob Phillips. Super Cool Jokes and Games for Kids. Harvest House Publishers, July 1, 2002, p. 72.

This document was translated from L^{A}T_{E}X byH^{E}V^{E}A.