Monday, November 3, 2014

Luck versus Skill

A fascinating concept in game design is that of luck versus skill. A lot of folks tend to present them as opposing ends of a dichotomy. More random means less skill, and more skill means there can't be as much random. This is a false dichotomy; the relationship between the two is far more interesting than that.

Richard Garfield, the creator of Magic: The Gathering, has a talk where he pontificates about luck in games and how they affect the outcomes of these games. One of the examples he uses to show that skill and luck aren't diametrically opposed is "Rando-Chess".

Imagine a game of chess where at the end of the game you roll a die, and if it's a 1, the winner becomes the loser and the loser actually wins. Now, ignore that voice in your head screaming that's unfair for a moment. Does it actually reduce the skill required to play the game? Everything about chess is still applicable: opening gambits, strategies, knowledge of the rules. Having all of that skill still increases your win-rate over time. It didn't make skill useless at all; however, it does moderate skill disparities.

If you have a game that's all skill, if you're equally skilled you'd expect to win 50% of the time. If you were more skilled, you'd expect to win most, if not all, the time. Adding a random roll at the end in the Rando-Chess game means that the weaker player now has a chance at winning, despite being the poorer player.

Now, Rando-Chess wouldn't be very satisfying to play. I'm pretty sure I'd flip a table or two when I lost due to the direct result of the random roll. Instead, most game designers embed the randomness in their games in other ways. Accuracy in TRPGs or tabletop strategy games, so even if you play the most perfect tactical game ever, you can still get hosed by missing that 99% chance to hit shot. Starting positions in games like Civilization, where you may end up with different resources necessitating different strategies. Deck building in games, where even if you've built the deck and know what's in it, you won't get the cards in the order you necessarily want them in.

But here's a twist where that interesting relationship between the two comes into play again: you can often reduce the effects of randomness by applying skill.

Here are some prime examples.

In a game like Magic: The Gathering or Hearthstone, when building your deck, you want to make sure said deck is as relatively focused as possible. When you draw your next card, you want to increase the chances that said card will be applicable to your overall strategy. This is also often why Card Advantage is very, very important to these kinds of games: because you're cycling through your deck faster, there's a higher chance you'll get the cards that you want, thus reducing the effect of randomness.

Purple has 5, 6, 9, and 10, whereas Red has 3, 4, 6, 8, 9, 10, and 11. Despite Purple having more points than Red, Red is arguably in the stronger long term position because they're less at the mercy of luck.
In Settlers of Catan, by diversifying the values your cities are adjacent to, you can reduce the effects of luck on your resource intake. If you only ever get resources on a 3, 6, and 8, you'll get hosed if the dice continually roll 9s and 4s. If you have as many different numbers as you can possibly get, then no matter what numbers show up on the dice, you're getting resources, which can be traded in for other resources.

In an MMORPG with trilogy-based real-time combat, like World of Warcraft, the things that usually kill tanks are unpredictable spikes of damage. As a tank or a healer, the best thing you could ever do for your tank's survival is the reduce the effects of randomness as much as possible and ensure the rate of incoming damage is as smooth as possible. Things like Active Mitigation and external cooldowns such as Hand of Sacrifice allow the tanks and healers to have some control over the variability of incoming damage.

Spreading out is a pretty standard response to "bosses use targeted AoE abilities"
A more visual example is the case where you know that a boss will use abilities at seemingly random. Let's assume you have 10 players facing a boss who will sometimes put a big circle of doom under a player. To reduce the amount of risk to the group as a whole, obviously the solution (skill) to apply is spreading out. At worst, only a single player will get nailed. 
Our left-most player gets hit by a circle of doom. Of course, she can just walk out of it here, but since nobody else was around, the potential for damage is reduced.
Make that harder by having the circles stay for the duration of combat, and now where you move to becomes more important. If you position yourself in a way that doesn't allow you an escape route (or another player does that), then you've left yourself at the mercy of RNG rather than using you skills to pick a better position to wait for the incoming attack.

Our left-most player gets boxed in by someone else moving nearby them. If either player had more awareness of their surroundings (a skill), they could have prevented trapping the left-most player.
Interestingly, this is why I'm extremely hesitant to say I got screwed by RNG in most boss fights. That's not to say there aren't badly designed fights out there where it is truly the case where randomness can screw you, but the careful application of skill can often mitigate or remove that "bad luck" entirely.

On the other side of the equation, you have games that are entirely luck: Chutes and Ladders (or Snakes and Ladders depending on where you live) has precisely zero decisions and precisely zero factors that are influenced by the individual.

If you made a game where the point was to kick a soccer ball the furthest, you have both physical skills (such as strength and accuracy), as well as mental skills (which way is the prevailing wind headed? What spin should I put on the ball?), so while at first blush it might not seem like there's any "skill" involved because it's a feat of physical prowess, there are definitely decisions occurring that could make or break a win even if the players aren't physically equally capable. Basically, a skilled player would use the wind to their advantage. An unskilled player would say they lost because they were unlucky due to the wind. To be fair, however, a strong gust of wind might actually alter the outcome of the match.

Randomness is a tool like any other in a designer's kit. It can be used to muddy the skill disparities between players, or to ensure that players don't get stuck in a rut where the exactly same strategy applies every single time. Players can fight randomness by applying skill, but ultimately they will likely never overcome it entirely (it's possible, if unlikely, for that 11 to be rolled in Settlers over and over again and it's the only number you don't have), so the skill muddying effects can still apply.


  1. To me, skill in MMOs has always come down to versatility; the greatest players in WoW played both PVE and PVP and generally tried to excel in any given situation. You can only hone your skills via variety and ( good ) randomness provides opportunities to do that.

    1. Randomness is often used as either an approximation of a human opponent (if you posit humans are just calculation machines with a little bit of data corruption that makes it harder to predict what they're going to do), or to ensure people don't fall into the same strategy rut by altering the battlefield/gameplay in a way that's different from the prior run.

      In short, absolutely!

  2. This was a good read as it clearly demonstrates why this is a false dichotomy.

    I think my favorite example are deck building games like Dominion. Similar to TCGs, card advantage plays a huge role, but the entire game is about building your card advantage despite the random obstacles thrown at you. Often that means employing cards that allow you to trash other cards, increasing your deck's efficiency. Too much, however, and your deck cannibalizes itself!

    Personally, I think the problem is more about manageable luck versus the destiny draw bullshit. For example, when a game allows the stars to align as it did sometimes for early implementations of Windfury in WoW, there's clearly no skill in the world that can mitigate a string of strung together attacks. It works fine for PvE, since unforeseen spikes can largely be expected and responded to (within some reason).

    I am with Syl. Versatility is key in a MMO because randomness makes a game more interesting/dynamic and that leads to players being able to act with their toolkit (skill) effectively over time (mastery) which leads to fun!

    1. Yeah, having a deck and hand size limit does put an upper cap on how effective Card Advantage can be. I've decked myself in Hearthstone a couple times, and I've certainly done it in M:tG (also, decking the opponent is the best way to win, just saying). Dominion, however, doesn't suffer from that. The best hand is one where you go through your entire deck in a single turn (which I have also done).

      But yes, I agree about manageable luck versus destiny draw. And you see that in TCGs as well with Mulligan rules. I think good randomness doesn't necessarily screw you or entrench you in a single event, but a string of bad (or good luck)? Eh, that's less likely so it makes it more okay in my mind. At least makes for a good story.

      An example where a single event makes a super interesting yet balanced difference to a game is House on the Haunted Hill. During the game, eventually someone will fail a haunt roll. Depending on the last card drawn and what room you're in, you get a different scenario where someone is a traitor, or no one is, and you're suddenly dealing with spiders, or a werewolf, or the house is collapsing into the nether. Really smart way of using random to radically alter gameplay without making it unfair.

    2. Exactly. These are all reasons why I love baseball more than other sports. You play against likelihoods and probabilities, not pitting your absolute strength/speed/etc. against someone else.

      You need skill, strategy, and luck to succeed!

    3. But baseball is sooooo boring to watch.

  3. "Starting positions in games like Civilization, where you may end up with different resources necessitating different strategies."

    Indeed, or even the map type matters. I've been playing Civ V a lot lately -- one recent game I did a random map where I wanted to try to expand fast with Liberty.

    ...except then I wound up on a small island and that killed fast expansion. And then there were all of like 2 decent spots to settle that I could actually defend. Really wished I had gone tradition with that!

    Soon as I saw I was trapped on an island I should have switched gears in expectation of not being able to expand much...and I didn't, and I paid the price versus probably being able to salvage the game.

    P.S. If you're playing Civ 5 these days, we should play a bit! Don't have BE yet.

    P.P.S. I also agree that baseball is boring to watch in and of itself. Fun at the stadium or with a group of friends to share the experience, but really dull otherwise.

    1. I've been playing BE a fair bit, but Civ V is still a blast. We should play soon, since the WoW expac will eat all my free time until December.

    2. Hit me up on Steam, ID should be Balkoth (if not, then magical_master).

    3. There's like 8 Balkoths on Steam. I picked the one that played Civ V recently. Hopefully it's the right one!