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Minmaxing - Is turn-based fun anymore?

Are turn-based games less fun when a programmer does his best to win?

Wesley Paugh, Blogger

February 6, 2012

6 Min Read

Why do turn-based games exist? Will they remain interesting to us forever given advances in computing power?

I ask because I have very little interest in playing chess, or learning Go, because I know I could just write a program to do a better job of either than I ever could manage on my own. Any turn-based game, and any real-time game whose only continuous parameter is time, can be min-maxed to find a single ideal move each turn. If both players make those moves, then both are playing optimally and a balanced game will end in a stalemate of some sort. Unbalanced games and games that leverage randomness cannot be said to be games of skill (at least, not between players that know how to play optimally) which, in my mind, makes them emphasize more the act of playing than the outcome (whether that outcome is a score or a win / loss state).

If players willingly choose to make different moves than the optimal ones, then the game being played is no longer the same; players are now playing the original game, and another game whose goal is not to win at, say, Chess, but to deceive their opponent into making much less optimal moves than he might, otherwise. That social game, I'll call it 'Deception',  can be factored out of Chess, Counter-Strike or any other game or even instance of two humans interacting. It should not be omitted from any critique of a game's quality (i.e., don't call Poker a great game because its rules are exceptional, call it great because its rules are compatible with so many metagames).

Any efforts to design games within turn-based, discrete-space limits and have the game be balanced and challenging are efforts to make the utility of game states less knowable, and the state space less traversable through thought. Becoming a better player in those games involves seeing through those obfuscation efforts and learning to better estimate which moves yield higher-utility states. Games become, very much so, solving a puzzle in the sense that there is a single, highest-utility sequence of moves you must figure out that guarantee stalemate in balanced games (or, if a player wins, the game may as well have been a single dice roll, as randomness could have been the only deciding factor). If you play against an opponent whose moves are deterministic (and a player that always plays optimal moves would be deterministic, for all intents and purposes), the game becomes indistinguishable from a sliding-block puzzle, for example.

I've never played Civilization games, but, to hear them described, they have added so many and so complex a set of legal moves that establishing utility becomes difficult. In the end, though, it's still just the same min-max puzzle as Chess or Tic Tac Toe, yes? Figure out the best move and play it, and assume your opponent will play his best move. If the move he plays isn't optimal, then one of two things has happened.
 
One option is that your opponent was not aware that his move wasn't optimal, because his means of assessing utility wasn't very good. If that's the case, continuing to make optimal moves guarantees victory, rather than stalemate, in balanced games.
The other possibility is that your opponent is playing both the original and a different social game like Deception. Even though Tic Tac Toe is a game humans can solve easily, an extremely clever player could conceivably win the game more often than others by playing social games like 'Deception' on top of it, and not all of the moves in 'Deception' would appear to interfere with Tic Tac Toe.

I should clarify, I'm not saying I have any problem with Civilization or Chess; there are surely certain people that enjoy studying how series of successive game states aggregate into 'strategies'. Nothing about playing the game to win is fun in and of itself, though; the 'decisions' we make are meaningless guesses at finding an optimal moves, and the fun is in studying and recalling information about the game, not playing it. Playing those games for fun means either accepting that you are solving a puzzle by crunching numbers on utility and game states (which I can't imagine anyone finding fun), or accepting that your goal in playing is to amuse yourself rather than to win. I suppose you could do a little of both, but the importance of the latter is where I truly believe new sources of fun will be found in games. Well, that, and the ability to include social games like 'Deception', which I have a hard time envisioning ever being min-maxable by human or computer.

This post is largely thinking out loud, but it's helped me put into words some of my feelings towards what games are really supposed to be doing, and what game design ought to entail. Rules, states, and systems are great, as they give context for play. But it's sounding more and more reasonable that, if all a game designer has as a goal is to devise a state-space generator and utility-estimator whose complexity is beyond the human mind's ability to traverse exhaustively, that designer will not necessarily make a fun game.

The problem with my thinking like this is that it defines games out of existence. Continuous-space games and real-time games can be examined as generalizations of turn-based, discrete games that only further complicate, rather than somehow magically eliminate, the ability to min-max game states to solve games as you would puzzles.

Now, I don't know of any designers that design by envisioning a state-space and transitions, and planning states with the goal of slowing down efforts to estimate utility. But! This is the sort of meaning I take from people (and there are a fair number of them) that talk of games as being 'interesting-decision generators' and calling for games to move away from visceral or aesthetic appeal and back towards board games and other more abstract games like Chess.

The trick of finding the right balance with other disciplines of game development is of much greater use. Examine games you design as though they were state machines, certainly, to assess and tweak your game's complexity, but it is important not to give too much development priority in creating the emergent depth of games like Go at the cost of enhancing other gameplay quality attributes (e.g. usability / UI design).


( For context, this post is coming after 6 months doing encounter design for a turn-based iOS game called 100 Trials )

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