Prismata Review

A few month’s ago I reviewed a game by David Sirlin called Codex. It is an attempt to convert a real-time strategy game, like StarCraft, into a card game. And it actually does a really good job (see the post for details).

I’ll try to not talk about StarCraft very long, because the words will be indecipherable to anyone who hasn’t played it (which is probably 99% of people reading this). There is a really old and interesting question about the game: if you strip away everything but the strategy aspect, is it still an interesting game?

This may sound weird to people unfamiliar with the game, because, well, it’s a real-time “strategy” game.

The first ridiculous thing when starting StarCraft is how much there is to learn. There’s probably close to a 100 hotkeys you have to know. There’s the tech tree structure. There’s around 60 units, each of which you should know cost, types of attacks, damage, health, shields, and what the spell-casting abilities are. Knowing those things, you’ll need to learn what counters what and why.

And you might be thinking, but I’ll just click through stuff during a game to find the information. There’s no need to memorize it. That brings up the other crazy aspect of the game: apm (actions per minute). You are going to have to have 200-300 apm (i.e. clicking or pressing a keyboard key 5 times per second on average for an entire 15+ minute match), so you just don’t have time to look stuff up during a match even though that information is available:

If you’re not a StarCraft player, hopefully you’re getting a sense of why the question doesn’t have an obvious answer. You have to play for months just to internalize the hotkeys and learn enough to get to the point of forming any sort of strategy.

If you strip out the memorization; If you strip out dividing the opponent’s attention and distracting them; If you strip out the fog of war; If you strip out having to execute 5 actions per second perfectly for an entire match: is there an interesting strategy game left? In other words, is the winner just someone who clicks faster?

Codex went a long way to answering that question in the affirmative. Sirlin brilliantly left in an aspect of the fog of war and tech trees. But the fact that it is a card game messes with the answer a little. There’s still some luck and some blind countering and some memorization to know what possible answers your opponent will have.

Okay, so this post is supposed to be about Prismata. To me, Prismata gives us a near perfect game for answering the question. There is absolutely no hidden information. All the units and their costs and their abilities are listed on the side at the start of the game. A beginner can play matches with slow enough time controls to carefully read all of this and formulate a plan before making moves.

As soon as your opponent buys a unit, it goes onto the board. So there is no random hidden information of shuffling it into a deck like Codex. Despite it’s appearance, Prismata is NOT a card game. There is no deck or randomness in gameplay at all.

The only randomness is in what units you are allowed to choose from during setup, and I think this is absolutely brilliant. In traditional strategy games like Chess or Go or even StarCraft, there are set openings that one must memorize to play at the top level because every game starts the same. This takes the strategy out of the opening.

In Prismata, every game is different. You have to look at the board you’ve been given and start planning a strategy on Turn 1. It’s a really exciting and fresh idea for a strategy game. It’s like if Chess or Go started with some randomized board state. You couldn’t go into a game with a plan to play a Queen’s gambit or the Kobayashi opening or something. You have to develop a plan on the fly based on the board. It’s a true battle of skill.

Before this review gets too far, I have to bring up the last comparison to Codex. Codex is a card/board game. There is no real online way to play. I played quite a bit by forum, and this might be tolerable for some people. The community is certainly very active, and you won’t have trouble finding a match. But it brought too much fatigue for me, and I stopped liking it for awhile.

Prismata is computer only (eventually through Steam and a separate client and web browser, though I’m not sure if all will continue to be supported after Steam release). If Codex had a computer version, it might compete for my attention. As it is, it’s a game that is played in person, occasionally.

Prismata has an excellent set of tutorials and basic bots and “story” to play through to get a newcomer up to speed. The game looks horrifically complicated, but it is actually very easy to learn and difficult to master. I promise if you play through the basic stuff, you’ll have a full grasp of the basics and even have a few basic strategic ideas. Do not be intimidated by a cluttered screenshot if this game sounds at all interesting to you.

Prismata is a game for people who like strategy and/or card games but who don’t like some of the ridiculous aspects of both. Many strategy games have too much hidden information to make good decisions or too much technical execution to execute a strategic plan. And card games, well, the online ones at least have way too much randomness. There’s also that super annoying way card games completely change every few months when new cards get released and you have to dump a ton of money into it to stay relevant.

Did I mention Prismata is true free to play? Since it’s not a card game, you’ll be playing the real game every game. Neither side will have an advantage merely from grinding out hundreds of hours or paying hundreds of dollars to unlock some legendary thing.

Right now, if you want to try it, you’ll need to request an alpha tester key here. It should release on Steam very soon, though, and I promise to reblog this with the link at the top to remind anyone interested.

Reviewing Sirlin’s Codex

I’m travelling, so this might not be the most thorough or polished review Codex deserves. Don’t take this as a reflection on the game.

The game can be learned in one or two playthroughs, but it will probably sound way more complicated when describing it in words. I’ll refer to Magic: The Gathering (MtG), Hearthstone, and Dominion. If you have absolutely no familiarity with any of these games, you may want to skip the post. But, you don’t have to have played any of them. If you’ve heard of MtG and vaguely know what a deckbuilding game is (Dominion), you’ll probably be fine.

Codex takes the core of MtG as it’s starting point. Each player has their own deck built from various colors. The colors tend to have themes that loosely follow MtG. Red focuses on haste and burn spells. Green is creature and growth spell based. Black uses skeletons and killing off creatures to get effects. And so on.

But that’s about where the comparisons stop. One of the most annoying aspects of MtG for me is that you can only attack the other player with your creatures. The opposing player has all these creatures on the battlefield and can even block with them, but the attacker can’t have their creatures attack them. It makes no sense, and forces really weird play to avoid bad trades. Also, after being damaged, creatures heal for the next turn. This makes healing a totally nonviable type of spell to design around.

Hearthstone basically fixes these two oddities by allowing creatures to attack each other, and damage persists across turns. This is also how Codex works. It opens up so many interesting decisions. Do I heal myself or do I heal my creatures? (It’s actually not that interesting. Answer: Always heal the creatures because your health isn’t as important as board presence).

In all these games, one must pay a cost to cast a spell or summon a creature. MtG builds these costs into the deck by forcing you to have “dead” cards (land). This means you can randomly get flooded by too much or screwed by too little. The ideal would be to play a land every turn to keep ramping up to better creatures until you hit an ideal amount, and then you never want to draw land again.

Since this is the ideal, Hearthstone just forces this to happen by giving you one extra mana per turn. It fixes these two MtG issues in one swoop. You never draw dead cards, and you can focus on strategically playing on curve without being at the mercy of random draw.

In a sense, this goes too far, because it eliminates some of the decision space. Codex draws on RTS games and hits a very interesting middle ground. You pay for cards with gold, and you always have the choice to increase the amount of gold each turn to play on curve. But unlike Hearthstone, there’s a cost to do it. You must convert a card in hand to a “worker.” This removes the card from the game and costs 1 gold, a startlingly high cost that after a few games becomes clear to always be worth it.

The more decisions that have to be made, the higher the skill cap. This one choice each turn is very interesting. Do you forego making a worker to have better card advantage, and 1 extra gold this turn; or is this too risky because the next turn your opponent will have more gold if they make a worker?

Another RTS innovation that increases the decision space is building tech buildings. Each turn you get to add two cards to your deck from a pool determined by your starting factions. This is the Dominion deck building idea. The point of this is that you can try to predict your opponents strategy and then add in cards to your deck to counter them. But maybe they were only feigning a strategy and you teched in a counter which they already countered. The mind games are real.

If you haven’t built any buildings, you can only use cards coming from Tech 0. If you spend money to build a building, you get to use Tech 1 cards and so on. This is often the hardest decision in the game for me. Tech 2 cards are really, really powerful. If one player starts playing them significantly earlier than another, they will probably spiral out of control to victory.

But building the structure to play these powerful cards pretty much wrecks a whole turn. In other words, if you build these too early, you might incur a cost so severe you fall behind and can’t catch up, even with the powerful new cards. If you build it too late, your opponent might just win with their powerful cards. It’s a super interesting and critical decision that has to be made by comparing economies, board state, card advantage, your current strategy, your opponent’s strategy and so on.

The last interesting innovation I’ll talk about is the fact that you have to have a “hero” in play to cast spells. This opens up a huge range of possible targets for attack. Do you kill the hero and cripple their ability play spells? Do you attack creatures for board advantage? Do you attack tech buildings so they can’t play their more powerful cards? Do you all-in and only attack the base in hopes of rushing a victory?

And this is only the half of it. There’s a board, so creatures can take up strategic positions. Heroes have abilities they get from levelling up. Some of the innovative card keywords are really clever, like Purple being about time manipulation. And I’m sure I’m missing dozens of cool ideas they’ve packed into this.

I’ll admit it is quite expensive to get the full thing, but it’s not a collectible or trading card game. The set is complete as is (and considering it’s priced at about 2 booster boxes of MtG cards, i.e. 1/(10,000+) of the cards in MtG, it’s hard to complain). Once you have all the cards (which come in the Deluxe version), you’re done buying cards for the game forever. The Core Set is priced at a standard board game price and gets you the complete Green and Red sets, and if this is interesting to you, you’ll get more than enough hours of play to make it worth it.

Overall, I couldn’t be happier. It’s like this game was designed specifically with me in mind. The game is really fun at a casual level, but really deep. I could see the game becoming quite competitive with how high the skill ceiling seems to be.

Draw Luck in Card Games, Part 2

A few weeks ago I talked about draw luck in card games. I thought I’d go a little further today with the actual math behind some core concepts when you play a card game where you build your own deck to use. The same idea works for computing probabilities in poker, so you don’t need to get too hung up on the particulars here.

I’m going to use Magic: The Gathering (MTG) as an example. Here are the relevant idea axioms we will use:

1. Your deck will consist of 60 cards.
2. You start by drawing 7 cards.
3. Each turn you draw 1 card.
4. Each card has a “cost” to play it (called mana).
5. Optimal strategy is to play a cost 1 card on turn 1, a cost 2 card on turn 2, and so on. This is called “playing on curve.”

You don’t have to know anything about MTG now that you have these axioms (in fact, writing them this way allows you to convert everything to Hearthstone, or your card game of choice). Of course, every single one of those axioms can be affected by play, so this is a vast oversimplification. But it gives a good reference point if you’ve never seen anything like this type of analysis before. Let’s build up the theory little by little.

First, what is the probability of being able to play a 1-cost card on turn 1 if you put, say, 10 of these in your deck? We’ll simplify axiom 2 to get started. Suppose you only draw one card to start. Basically, by definition of probability, you have a 10/60, or 16.67% chance of drawing it. Now if you draw 2 cards, it already gets a little bit trickier. Exercise: Try to work it out to see why (hint: the first card could be 1-cost OR the second OR both).

Let’s reframe the question. What’s the probability of NOT being able to play a card turn 1 if you draw 2 cards? You would have to draw a non-1-cost AND another non-1-cost. The first card you pick up has a 50/60 chance of this happening. Now the deck only has 59 cards left, and 49 of those are non-1-cost. So the probability of not being able to play turn 1 is ${\frac{50}{60}\cdot\frac{49}{59}}$, or about a 69% chance.

To convert this back, we get that the probability of being able to play the 1-cost card on turn 1 (if start with 2 cards) is ${\displaystyle 1- \frac{50\cdot 49}{60\cdot 59}}$, or about a 31% chance.

Axiom 2 says that in the actual game we start by drawing 7 cards. The pattern above continues in this way, so if we put ${k}$ 1-cost cards in our deck, the probability of being able to play one of these on turn 1 is:

${\displaystyle 1 - \frac{(60-k)\cdot (60-k-1)\cdots (60-k-7)}{60\cdot 59\cdots (60-7)} = 1 - \frac{{60-k \choose 7}}{{60 \choose 7}}}$.

To calculate the probability of hitting a 2-cost card on turn 2, we just change the 7 to an 8, since we’ll be getting 8 cards by axiom 3. The ${k}$ becomes however many 2-cost cards we have.

Here’s a nice little question: Is it possible to make a deck where we have a greater than 50% chance of playing on curve every turn for the first 6 turns? We just compute the ${k}$ above that makes each probability greater than ${0.5}$. This requires putting the following amount of cards in your deck:

6 1-cost
5 2-cost
5 3-cost
4 4-cost
4 5-cost
3 6-cost

Even assuming you put 24 lands in your deck, this still gives you tons of extra cards. Let’s push this a little further. Can you make a deck that has a better than 70% chance of playing on curve every turn? Yes!

9 1-cost
8 2-cost
7 3-cost
7 4-cost
6 5-cost
6 6-cost

Warning: This mana curve would never be used by any sort of competetive deck. This is a thought experiment with tons of simplifying assumptions. The curve for your deck is going to depend on a huge number of things. Most decks will probably value playing on curve in the 2,3,4 range way more than other turns. If you have an aggressive deck, you might value the early game. If you play a control deck, you might value the later game.

Also, the longer the game goes, the less cards you probably need in the high cost range to get those probabilities up, because there will be ways to hunt through your deck to increase the chance of finding them. Even more, all of these estimates are conservative, because MTG allows you to mulligan a bad starting hand. This means many worst-case scenarios get thrown out, giving you an even better chance at playing on curve.

This brings us back to the point being made in the previous post. Sometimes what feels like “bad luck” could be poor deck construction. This is an aspect you have full control over, and if you keep feeling like you aren’t able to play a card, you might want to work these probabilities out to make a conscious choice about how likely you are to draw certain cards at certain points of the game.

Once you know the probabilities, you can make more informed strategic decisions. This is exactly how professional poker is played.

Draw Luck in Card Games

Every year, around this time, I like to do a post on some aspect of game design in honor of the 7DRL Challenge. Let’s talk about something I hate: card games (though I sometimes become obsessed with, and love, well-made ones). For a game to be competitive, luck must be minimized or controlled in some way.

My family is obsessed with Canasta. I don’t get the appeal at all. This is a game that can take 1-2 hours to play and amounts to taking a random hand of cards and sorting them into like piles.

I’ve seen people say there is “strategy” on various forums. I’ll agree in a limited sense. There is almost always just one correct play, and if you’ve played a few times, that play will be immediately obvious to you. This means that everyone playing the game will play the right moves. This isn’t usually what is meant by “strategy.” By definition, the game is completely decided by the cards you draw.

This is pure tedium. Why would anyone want to sit down, flip a coin but not look at it, then perform a sorting task over and over for an hour or more, stop, look at the result of the coin flip and then determine that whoever won the coin flip won the “game.” This analogy is almost exactly the game of Canasta. There are similar (but less obnoxious) bureaucratic jobs that people are paid to do, and those people hate their job.

Not to belabor this point, but imagine you are told to put a bunch of files into alphabetical order, and each time you finish, someone came into the room and threw the files into the air. You then had to pick them up and sort them again. Why would you take this task upon yourself as a leisure activity?

I’ve asked my family this before, and the answer is always something like: it gives us something to do together or it is bonding time or similar answers. But if that’s the case, why not sit around a table and talk rather than putting this tedious distraction into it? If the point is to have fun playing a game, why not play a game that is actually fun?

This is an extreme example, but I’d say that most card games actually fall into this pure coin flip area. We get so distracted by playing the right moves and the fact that it is called a “game” that we sometimes forget the winner of the activity is nothing more than a purely random luck of the draw.

Even games like Pitch or Euchre or other trick taking games, where the right plays take a bit more effort to come up with, are the same. It’s a difficult truth to swallow, but the depth of these games is so shallow that a few hours of playing and you’ll be making the correct moves, without much thought, every single hand. Once every player makes the right plays, it only amounts to luck.

It’s actually really difficult to design a game with a standard deck of cards that gets around this problem. I’ve heard Bridge has depth (I know nothing of the game, but I take people’s word on this considering there is a professional scene). Poker has depth.

How does Poker get around draw luck? I’d say there are two answers. The first is that we don’t consider any individual hand a “game” of Poker. Obviously, the worst Poker player in the world could be dealt a straight flush and win the hand against the best Poker player in the world. Skill in Poker comes into play over the long run. One unit of Poker should be something like a whole tournament, where enough games are played to overcome the draw luck.

Now that we aren’t referring to a single hand, the ability to fold with minimal consequences also mitigates draw luck. This means that if you get unlucky with your initial cards, you can just choose to not play that hand. There are types of Poker that straight up let you replace bad cards (we’ll get to replacing in a moment). All of these things mitigate the luck enough that it makes sense to talk about skill.

Another card game with a professional scene is Magic: The Gathering (MTG). Tournament types vary quite a bit, but one way to mitigate draw luck is again to consider a whole tournament as a unit rather than an individual game. Or you could always play best of five or something.

But one of the most interesting aspects is the deck itself. Unlike traditional playing cards, you get to make the deck you play with. This means that over the course of many games, you can only blame yourself for bad drawing. Did you only draw lands on your first turn for five matches in a row? Then maybe you have too many land cards. That’s your fault. Did you draw no land many times in a row? Also, your own fault again. Composing a deck that takes all these probabilities into account is part of the skill of the game (usually called the “curve” of the deck).

Here’s an interesting question: is there a way to mitigate draw luck without having to play a ton of games? Most people want to play something short and not have to travel for a few days to play in a tournament to test their skill.

In real life, replacing cards is obnoxious to implement, but I think it is a fascinating and underutilized rule. The replacement idea allows you to tone down draw luck even at the level of a single game. If your card game exists online only, it is easy to do, and some recent games actually utilize this like Duelyst.

Why does it work? Well, if you have a bad draw, you can just replace one or all of your cards (depending on how the rule is worded). Not only does this create strategic depth through planning ahead for which cards will be useful, it almost completely eliminates the luck of the draw.

I really want to see someone design a card game with a standard deck of cards that makes this idea work. The one downside is that the only way I can see a “replace” feature working is if you shuffle after each replacement. This is pretty annoying, but I don’t see a way around it. You can’t just stick the card you replace into the middle of the deck and pretend like that placement is random. Everyone will know that it isn’t going to be drawn in the next few turns and can play around that.

Anyway. That’s just something I’ve been thinking about since roguelikes have tons of randomness in them, and the randomness of card games have always bothered me.