About the All-in or Fold Game

Overview

This article will provide a brief introduction to the All-in or Fold game (a Texas Hold’em game where you only choose between All-in or Fold) implemented on this blog:

including how to play it, as it has been ported to the Android app “Exotic Poker” (the iPhone version is under development and is scheduled for release around June-August 2026). I won’t be discontinuing the game on the blog, but I plan to only implement future feature enhancements in the mobile app. Therefore, if you’re interested, I’d appreciate it if you would use the mobile game. The link to the game is below.

I plan to write articles on this blog in the future that will briefly explain the rules and how to play each game available on “Exotic Poker”.

How to Play the Game

The game installation process is the same as for any other app. Upon first launch, a screen will appear requesting your agreement to the terms of service; check the box to agree and press the “Agree” button. Repeated installations and uninstallations may cause the app to crash and become unplayable. In this case, you can clear storage from the app’s information screen and then launch the app. The app internally manages anonymous user IDs, but currently, this is not used for anything other than saving stats during multiplayer, so you can use it without worry (uninstalling the app will reset both the user ID and your stats). The author does not collect any information that could identify individual users, so please feel free to use the app without worry.

 Tapping the title screen will take you to the menu screen, where you should press the “Game” button. The game settings for playing All-in or Fold games are as shown in the following screenshot.

You can set your preferred conditions for Buyin (Stack size), Ante, and number of players. The play log is intended to record your actions for a future AI algorithm that mimics your behavior history; however, this function is not currently working, so you don’t need to check it.

 Pressing the “Play” button will launch the following game screen.

One slightly confusing aspect is that in All-in or Fold, if you lose, your stack immediately drops to zero and you’re forced to leave the game. To avoid this, the player’s balance is displayed as a bankroll. You start with 10 times your stack, and you play the game to increase this. In a 10bb game, 1bb = 100, chips when going all-in = 1000, and bankroll = 10000. The values ​​enclosed in boxes on the screen correspond to these values.

 The operation is simple: if you think you can win, select All-in; if you think you can’t win, select Fold. If you want to see the strategy used by the AOF Model (the optimal strategy estimated by an algorithm called CFR) as a recommendation, a checkbox will appear when it’s not your action, so check it.

The recommended action frame will now flash green. This is useful for practicing Push or Fold, for example.

 The optimal strategy discussed in the following article is used for games with up to four players.

Five or more people are using similar strategies. Specifically, they are as follows:

• If there are no players all-in in front of you, and there are three or more players behind you, adopt the CO strategy for when there are four players.
• If there is one player who has gone all-in in front of you and there are three or more players behind you, adopt the BTN (CO all-in) strategy as in a 4-player game.
• If there are two players ahead of you who have gone all-in and there are three or more players behind you, adopt the SB strategy (CO and BTN go all-in) as in a 4-player game.
• If there are three players ahead of you who have gone all-in, adopt the BB strategy (CO, BTN, SB are all-in) as in a 4-player game.
• If there are four or more players who have gone all-in before you, only go all-in with AA or KK; fold with everything else.

While not necessarily the optimal strategy, it appears to be a strategy relatively close to human judgment. Since the optimal strategy involves folding many hands, it might become boring with a small number of players. However, it’s suspected that it would still resemble a realistic strategy even with 9 players. Therefore, if you want a purely gambling-like experience with more all-in bets, increasing the number of players or setting a higher ante would likely enhance the game.

Summary

This article explains how to run a game equivalent to the All-in or Fold game in “Exotic Poker.” The All-in or Fold game for Texas Hold’em seems to be almost complete, so there may not be many further expansions. For some variations such as Short Deck Hold’em, Omaha, and games with jokers (Joker Wild, Joker as a Bug), I would like to diligently calculate and implement the optimal strategies for the All-in or Fold game, just like with Texas Hold’em.