Show HN: Card game where players write their own cards that get parsed into code

Show HN: Card game where players write their own cards that get parsed into code(app.wordbots.io)

114 points by alnis 3 years ago | 26 comments

Wordbots is a long-running side project I've been working on on-and-off for the past ~7 years that I finally feel comfortable enough with to share with the HN community.

It's an online tactical card game (inspired by games like Hearthstone and Magic: the Gathering), where players write their own cards in natural language, that gets parsed down to JavaScript. The English-to-JavaScript translation is handled by a semantic parser operating on a hand-crafted CCG grammar – kind of an “old-school” approach in this age of LLMs but one that performs quite well on the very constrained language of Wordbots cards.

The resulting game gets pretty wacky as players can create all sorts of cards, though there are some game formats that try to produce more balanced gameplay as well (e.g. one format in which both players shuffle their decks together, and various draft formats).

If you're curious about how it all works, I made a write-up about it here: https://app.wordbots.io/how-it-works

And if you want to chat about Wordbots beyond this thread, please don't hesitate to join our discord at https://discord.wordbots.io/ . I'd love to hear any and all feedback.

-Alex

lcnPylGDnU4H9OF 3 years ago |

I don't like competing so my first thought was to make a card which says, "You win the game." Is that possible, ostensibly with great cost, or is there some restriction on the effects? I believe MTG card effects often directly translate to a certain "mana" cost so it can be determined (in most cases) if a card is "overpowered" for its cost. Does this have some mechanism which ties effect to cost?

(I also appreciate the "old-school" approach in this case; I suspect it actually makes it easier to determine that the intended card is invalid.)

Edit: I tried, and I guess it is able to understand that. Nothing which seems to tie that to a cost, though. That makes sense as you'd effectively have to define a game system while this is crowdsourcing that to the community. I imagine the intention for play (if there really is one) is to have players agree on a set of cards to use.

alnis 3 years ago | |

You can definitely make an Action card with the text "You win the game" :-)

Wordbots doesn't have a built-in mechanism to enforce cards being at a "fair" power level. We initially had a few ideas for how to do it: some kind of machine-learning approach to determine how much "energy" a card should cost to play based on its text and stats, or having a server constantly simulating games between AI players with various cards to see how effective cards are in practice, or even a market-based mechanic where cards could be traded for in-game currency and how valuable a given card was would determine it's a "fair" card or not.

All of these approaches were ultimately abandoned as too complicated. Instead, we opted to just prioritize game formats where both players are equally likely to have access to any given card in-game:

  - In the Mash-up format, both players build a deck made up of any cards they want, but the two decks are shuffled together into one big deck that both players draw from.
  - In the Set format, players build their own separate decks but have to choose cards from a given "set" of cards curated by a player (and ostensibly the cards within a set should be roughly balanced).
  - In the draft formats (Set Draft and Everything Draft), both players are drafting from the same pool of crads.

This way, overpowered (and underpowered) cards can still be created by players, but at least in these game formats, both players would be equally likely to draw said overpowered cards.

digging 3 years ago | | |

That's clever and elegant, well done. I'm really interested, especially since it turns out to be more than just a ChatGPT front-end.

jstarfish 3 years ago | | |

I started making a game like this 7 years ago too. Congrats on your release :)

What I figured was to make there be a cost for using any card, pinned to the number of targets affected, amount of "force" applied, and one or more resources (life, energy, time, space).

Or an equivalent-exchange/extreme-couponing system of some kind. "To destroy the universe, you must first destroy something of equal or greater value." This can deadlock the game though.

After "heat death of the universe" cost too much to play, the workaround ended up being "wait for all other players to die of natural causes" (hadn't implemented time cost yet).

stonegray 3 years ago | | |

Could be interesting to see if you can make cards that only one player can use, such as “win the game if this card is played while the seconds of utc time matches the following hmac sum, otherwise lose the game”

Then you’ve got a 1/60th chance of your opponent using it.

Tourniquet 3 years ago |

Hi, My son has taken a shine to this after I sent him the link (he's up to 100 cards now...). Online, drafting, and the most important bit - user created content (he'd have been as happy with a traditional editor for the cards rules, but has had fun trying to convince the parser to do his bidding).

The Discord link is timing out for me. Hopefully you don't mind a brain dump here.

He had one feature request - the ability to restrict the number of Rare/Uncommon cards to be included in a deck built off of a given set (if that makes any sense).

Also, we hit a few bugs. One time we had a major state desync - on one player one team was entirely wiped out with a given card play, whereas on the other it had no/limited effect. From that point, the games diverged in their entirety - including the log. It was only because we were sat next to each other we even knew.

Some form of hashing of the engine state and comparisons every play could ensure that at least a desync identified (which would hopefully lead to a fix).

Another time, the 'End Turn' button was unresponsive for one player, and we instead had to force a draw.

He had an issue with a card he created that read "when you draw a card, ...", which was triggering when the opponent drew too.

The final thing is more of an irritation, which is the 'Activation' overlay can make it hard to move/attack to the hex immediately to the right.

Otherwise, great game and it's obviously a labour of love. Jist hope for a bit more interest and player activity.

mdaniel 3 years ago |

That looks neat, thanks for sharing. Speaking of sharing, it seems your repos are missing a license file (and the source files themselves don't have a licensing block that would also serve the same purpose).

I would also recommend linking to https://github.com/wordbots/wordbots-core/blob/v0.20.0-beta/... since the app.wordbots.io version seems to boot up some horrific amount of javascript or something, because the gears just sit there for about 15 seconds before the content finally shows up

Separately, do you know if the vocabulary for wordbots would tolerate the vocabulary for M:TG? IOW, is it possible to "port-over" some of the cards?

alnis 3 years ago | |

Oops, lack of licenses was my bad - good catch! Just added LICENSEs to clarify that both the game (https://github.com/wordbots/wordbots-core) and the parser (https://github.com/wordbots/wordbots-parser) are MIT-licensed.

alnis 3 years ago | |

Regarding M:TG vocabulary, Wordbots's syntax is a little bit different but a lot of the same effects are possible. For example, M:TG's Flametongue Kavu's "When Flametongue Kavu enters the battlefield, it deals 4 damage to target creature." becomes "Startup: Deal 4 damage to a robot" in Wordbots.

Some of the cards that people have been making so far in Wordbots are rough reinterpretations of cards from other games (M:TG, Hearthstone, Faeria, etc). Of course, many cards from these games wouldn't be possible to reimplement in Wordbots, as it doesn't have anywhere near the breadth of mechanics that these more-sophisticated games do. But also, there are some mechanics that are only possible in a game like Wordbots – such as https://app.wordbots.io/card/cnrssvyxfsp: > Replace "1" with "2", "2" with "4", "3" with "6", and "4" with "8" on all cards in your hand.

_raoulcousins 3 years ago | | |

This would work in Magic: Arena digital-only formats using the perpetual mechanic plus a variation of the text on a card like Magical Hack.

mdaniel 3 years ago |

Also, while not related to Wordbots, Alex has a cool JS sandbox-escape-y game https://alexnisnevich.github.io/untrusted/ (https://github.com/AlexNisnevich/untrusted#license CC-BY-NC-SA 3.0) that I thought was fun and you might, too

zomglings 3 years ago |

I like the game itself - it feels well balanced when you are playing single-player mode with built-in cards only.

But creating your own cards is an INCREDIBLY frustrating experience. This is a robot I tried to create (sumbot):

"This robot's attack, speed, and health are the sum of the attacks, speeds, and healths respectively of all other robots in play."

It didn't understand the words: "are", "sum", "speeds", "healths", "respectively".

Very restrictive dictionary and grammar. It pissed me off at a deep level and I probably will step away from this game.

Maybe integrate with an LLM (such as GPT4) to accept card descriptions?

It seems I can set an arbitrary cost for my cards? How do you balance the game when it involves custom cards?

One strategy would be to give each player a deck consisting of their cards and the opponents cards. So if someone made a really imbalanced card, they would have a 50-50 chance of having it used on them.

whynotkeithberg 3 years ago |

Incredibly cool! It's not normally my type of game but I am going to try this out for sure.

htaler 3 years ago |

I love the idea, and I'm going to try it out!

digging 3 years ago |

Weird bug I noticed (and I might have missed a better place to report it): The parser got stuck on the word "praction" in the phrase "When this robot deals damage to another robot, prevent all damage that would be dealt to this robot."

"Praction" comes after the comma in that phrase, apparently?

alnis 3 years ago | |

Hah, this is the keyword substituter incorrectly substituting "event" -> "action" (Action cards were called Event cards in an earlier version of the game). I'll fix that, but in any case, there's not any notion of preventing future damage currently.

P.S. Discord (https://discord.wordbots.io/) or GitHub (https://github.com/wordbots/) would be the best place to report issues like this at the moment.

habitue 3 years ago |

This is really cool, and actually I think LLMs would be a great fit: they can generate your constrained language from more freeform language input by the user. Might make it easier to get into, and you've done the hard work already by specifying a language for the card rules

MisterTea 3 years ago |

Neat idea. Unfortunately it knows nothing about infinite squirrels.

jamilton 3 years ago | |

The first card I made was "Startup: Create a copy of this robot in empty adjacent space", which immediately filled the board. Not quite infinite, but similar!

- In the Mash-up format, both players build a deck made up of any cards they want, but the two decks are shuffled together into one big deck that both players draw from. - In the Set format, players build their own separate decks but have to choose cards from a given "set" of cards curated by a player (and ostensibly the cards within a set should be roughly balanced). - In the draft formats (Set Draft and Everything Draft), both players are drafting from the same pool of crads.