Zugzwang

A great example I love showing people is Alpha Zero's infamous "Immortal Zugzwang Game" against Stockfish [0]. Stockfish gets utterly annihilated in a trap that seemingly springs out of nowhere, though of course the reality is that Alpha Zero was actually really in control the entire time.

[0] https://www.youtube.com/watch?v=lFXJWPhDsSY

In German language, the word Zugzwang is also often used figuratively to describe a situation in which you are forced to take (unwanted) action due to external circumstances.

Example from recent news: Most online shops offer Black Friday deals. The ones that don‘t are „under Zugzwang“ to join them.

Another German named situation is zwischenzug, which is an intermediate move.

If your opponent makes a threat against your piece, instead of making the expected move to block, move, capture, etc; you can instead temporarily threaten one of your opponent's pieces elsewhere as long as it has a greater value, this forces your opponent to suddenly act defensively to protect their piece, which if exploited correctly can put you in a better position. You will still have to answer your opponent's original attack and defend your original piece but now you have some extra compensation.

Basically you are exploiting the fact that your opponent thought they had played a forcing move and so they probably didn't consider the effect on other parts of the board.

Another interesting zugzwang situation is the game of animal shōgi [0], a simplified shōgi game that is strongly solved and found to be zugzwang position from the start.

[0]: https://en.m.wikipedia.org/wiki/Dōbutsu_shōgi

I'm a big fan of many Michael Brough games like Imbroglio, 868-HACK, and Cinco Paus because of how well he incorporates zugzwang into his designs. They always end up being these tiny, delightful challenges.

For German learners: It‘s a compound word. In German, and in English to some extent, you can join words to create a new word, e.g. Abstimmungsbekanntmachung (election notice).

Here’s a game which ends with a Zugzwang:

https://www.chessgames.com/perl/chessgame?gid=1008255 (future world champion Botvinnik vs Thomas; Nottingham 1936)

In the game, at the end, black is now, because of Zugzwang, forced to advance and weaken his f pawn. In a chess variant where players could pass instead of moving, it would be drawn, but since black must move, it is won for white.

White now simply has to move his king across the board, use it to take the now unprotected f pawn, then use the knight and king to take black’s b pawn, then promote one of his pawns to checkmate the black king.

Black wisely resigned.

I've played a lot of Hearthstone over the years and it has a concept similar to putting someone in check in Chess: Reducing their health to where one or two hits can kill them. Minions in Hearthstone can attack the opponent's minions or the opponent themselves - and most decks try to do the former efficiently (value-trade) and only attack (the opponent's) 'face' if they can't (either because all enemy minions are gone or there are no good trades to be had). The reason for this is that each player starts with a pretty big pool of health, so bringing that down to 0 must be a long term goal and going for that too greedily will cause you to lose board control and never get there. Only the most aggressive decks break this rule ('face is the place' goes the aggro motto). But interestingly one of the skills of the best players when playing slower decks is to know when to 'break character' and just go for 'face damage' instead even if it only puts the opponent low on health rather than outright killing them. At that point, the opponent is forced to make any trade they can in order to protect the little life they have left - they are in check. You 'reframe the conversation' by putting your opponent on their back heel.

Anyways, reading about Zugzwang made me wonder if there is a similar concept in Hearthstone too. And coincidentally, the latest expansion comes with a card that kinda fits the bill [1]. It generates powerful minions for you whenever you take damage, but is itself a minion with a lot of health, so it's hard to take down. When played against an aggressive deck with a lot of small minions, they get the choice of 1) Doing what they normally would do - attack your face - resulting in building you an army that would win you the game in a turn our two 2) Trading into the big minion to try to get rid of it - these are very inefficient trades and likely to not even succeed this turn or 3) Do nothing - which is probably the last thing they want to do, as the window of opportunity for an aggro deck to win gets smaller over time.

Obviously having this as a specific card isn't as elegant as the way this can be generated from the existing rules with a specific board state in chess, but I find it interesting to see how many of these more advanced game concepts can be put into a more casual game.

[1] https://hearthstone.gamepedia.com/Zzeraku_the_Warped

You can construct a cool game out of non-transitive dice that does this on the very first move but in a completely counter-intuitive way.

https://en.wikipedia.org/wiki/Nontransitive_dice

An extremely rare zugzwang with 10 pieces +kings and pawns on the board. https://en.wikipedia.org/wiki/Immortal_Zugzwang_Game

Poker has the concept of positional advantage. Acting later is an advantage because you gain more information from your opponent. Although chess is a total information game and doesn't have this phenomenon, the player at turn can still be at a disadvantage due to circumstance.

May be it is not a coincidence that this word came up in one of the episode in season 4 of Billions[0].

[0]: https://en.wikipedia.org/wiki/Billions_(TV_series)

And from that we can conclude that when someone has nothing to lose (and/or nothing they expect or hope to win) - one can not be “in Zugzwang”. That is, they might be moving, but their situation can not get worse.

The game of Go played on a 2x1 board apparears to be zugzwang right from the start, where any first move played is bad, due to the ko rule.

Since Go allows passing it's not a real zugzwang though...

Zugswang happens in software too: when your software project is done but people think it is dead because it has not been updated in 18 months...

This comes up in The Yiddish Policeman's Union by Chabon, an unique noirish alternate history dealing with chess and culture, among other things.

Zugzwang doesn't appear in Go game that often as in chess, even though it's much more complex game.

Americans call this up shit Creek without a paddle