my friend designed a really good card game and i was able to implement it in 24h (part 1)

the Duel of the Arcana board mid-game: Seraphine vs Mortessa, a spell called Lost in Shadows on the stack, hands, sources, and a long game log down the right side

My friend designed a really good card game, as of writing you can find it here: https://arcana.cool
The repo is here: github.com/levityproducer/duel-arcana-client

(Part 1 is about my thoughts on the game. Part 2 will be my thoughts on implementing the game, which was extremely fun)

From the Rules:

Duel of the Arcana is a two-player card game simulating a duel between mages. There are no turns. Instead, the two of you trade single actions back and forth — drawing breath, gathering power, and hurling spells onto a shared stack where speed decides who gets the last word.

The most central inspiration is old-school Magic: The Gathering. I think it delivers extremely well on a very refined old-school MTG experience, while also introducing some great new core ideas (the speed system).

a text conversation: "This game seems like extremely uncasual mtg. For those who love the stack" — "yes thats correct. it has Storm lol"

I won't really get into the rules in this blog post, but here are some things I like:

I really like the mana system -- any card can be “channeled” as a source. It's basically just like an MTG basic land: you tap it it can only produce mana of one color (but you get to pick the color when channeling). You untap it during an untap step (rest).
- This is very cool! It has many cool qualities. It reduces lame variance from draws hugely: You can't get too many / too few / wrong color lands. But color restrictions still end up mattering a lot. a card that costs 1M really is a lot easier to cast than one that costs MM.
- This also means you can have cards in your deck that are a lot more situational, because at worst it's a source. I think this is really cool and more interesting than a sideboard system.
- Despite decks being more consistent in terms of mana production, you can only have 3 copies of a card in a 50 card deck. So in terms of your actual options it can be a bit more varied than MTG. In practice this just feels so much better and more interesting of a form of draw variance.
  - Also on variance: it uses the Hearthstone style mulligan where you redraw N cards of your choosing, once. Which I consider a lot better.
Sort of like Legends of Runeterra, there's a lot more than just 5 colors. And you get to pick 2 for a deck. Again I think this is awesome. Each color feels like it has a quite interesting identity and I end up thinking a lot about different combos. Very cool!
Noah was able to do a pretty darn good job generating art for the game, it's pretty cohesive. I know he has stuff he wants to change and I would too, but it's very serviceable and doesn't feel WIP at all. Good job AI.
The primary action system that decouples playing things, drawing, and untapping, is super interesting and fresh. Haven't seen any other game do that.

So far the level of polish and balance is really amazing for a game that Noah has barely had time to playtest, that has 200(!) cards. I am very impressed. It's really such a cool gift when somebody designs a great game.

OK I am realizing as I write this that I don't have much to say except the game is good. I wish I could do a better job illustrating what cool moments exist in the game. I guess I should do a case study on some decks I built.

My first deck, “fuck you”

When I look at a new card game, the first thing I do is try to scan for any cards that seem broken.

There are a few things that tend to be very strong in any MTG-ish game; stronger than they would seem at first glance, so strong that they tend to cause balance issues. These are:

Fast mana
Drawing 3+ cards really cheaply (remember, a card that draws 3 cards is twice as good as a card that draws 2, since it's +2 net cards vs +1)
Cards that don't cost anything to cast
Mana destruction (can be devastating early into the game)
Extra turns

Cards are organized in the deckbuilder by color and cost. So the 0-1 cost Fire cards are the first I read:

the card library showing six cheap Fire spells: Burning Ritual, Every Soul Aflame, Static Shock, Lava Spike, Ignite, Set Your Heart Alight

Out of these I noticed:

Every Soul Aflame — 0 cost: on cast, each player gains Burned 2

Set Your Heart Alight — on cast: you gain Burned 2, then channel the top N cards of your deck as Fire sources, where N is your Burned value

Burning Ritual — 0 cost: on cast, channel the top card of your deck as a Fire source; destroyed when this spell leaves the stack

Hm, that's a lot of fast mana! You could combine Every Soul Aflame with Set Your Heart Alight and get crazy amounts of mana! And Set Your Heart Alight combos with itself!

I did a bit of testing and yes, rapidly getting to a state where you're in a chain (and can therefore cast without spending further actions) with 4-6 mana up is pretty feasible. In MTG having 4-6 mana on turn 2 is extremely good and could usually parlay into a victory. So what kind of stuff can I do with this mana?

One thing that stood out to me is Wildfire

Wildfire — deal 4 damage to each player; each player sacrifices two mana sources

-- since we can sacrifice mana sources that were temporary anyway, this is asymmetrically good for us and quite bad for the opponent. So that seemed good, but it's just 1 card.

Another issue is that if I'm spending cards on fast mana, then I don't have as many cards left over to play. And even if I do, if they don't win the game, I'm just sitting empty handed, which is almost always terrible in these kinds of games (your options are super constrained, and at the mercy of whatever happens to be at the top of your deck).

So how about card draw? Fire has several effects that draw cards, but are only good if you have few cards in hand. So that's interesting.

Flame Frenzy — each player discards their hand, then draws four cards

In particular, this one could have the dual purpose of keeping the party going + hurting my opponent.

For the most part, though, Fire does direct damage. So the most obvious application of this fast mana is to just make a deck that's really good at dumping its hand without needing to take the time to channel anything. The lethality of this compared to a slower strategy which channels things is a bit hard to calculate without running simulations (more on that later).

Immolate — deal 6 damage to target player; 8 if you cast another Fire spell this chain

Alright well what else is really good to do proactively, particularly in the first few turns? There's land destruction and there's discard.

the card library filtered by "discards": Flame Frenzy, Biblioclasm, Spiral of Doubt, Lost in Shadows, Echoing Dirge, Knife in the Dark, Nihilism, Domination, Mind Spike, and more

Ok, this shadow color does some discarding! What else is going on here?

(At this point I should mention each color has one Hero. Your deck is 2 colors and your Hero has to be one of those colors. Here's the Fire one:)

Ashka Stormheart — the Fire hero. Activated: deal 1 damage to target player, counts as casting a spell. Passive: your second spell each chain deals 1 damage to your opponent.

Ok and what about the Shadow hero:

Mortessa the Collector — the Shadow hero. When you cast a spell, you may exhaust Mortessa and pay 2 health to make it cost S less. Whenever an opponent discards a card, they lose 1 health.

Wow, more fast mana built right into the Shadow hero! And the passive reconciles the discard plan with our burn plan. Interesting!

Oh wow, that's basically Ancestral Recall!

Gains From Trade — draw three cards, you lose 3 health

Magic: The Gathering's Ancestral Recall — draw 3 cards or force opponent to draw 3 cards

Dredge Up Darkness — channel up to three cards from your discard pile as Shadow sources; destroyed when you next take a primary action; you lose 2 health

Magic: The Gathering's Dark Ritual — add three black mana to your mana pool

And that's basically Dark Ritual! And it works with Wildfire!

“Neat”, I am thinking. This Shadow stuff seems strong! So then I made a stupid deck with these cards in it and named it “fuck you” since I am trying to make an aggressive deck that isn't fun to play against.

I also asked Claude to make an aggressive deck and here is what she came up with. She even did a bunch of simulations and showed hers was generally faster than mine, though mine would occasionally win in only 3 actions (wow!). At this point I take some time to add support for human-vs-MCP. It works pretty good, yay! I wasn't able to find logs of the first game we played, so here's the second (the first was cuter unfortunately, she ended every message with 🔥)

Claude's play-by-play over MCP: mulligan choices, channeling Static Shock as a first Fire source, and a quick status while waiting on the opponent's pass

I expected to win but it turns out when playing against another Fire deck you don't want to constantly be dealing damage to yourself, so I was kind of obliterated.

Oops. So regardless of how good the deck might be in general, it seems really bad against a classic Burn deck. I want a deck that is good against everything, though, so it's time to build another.

See you next post!

P.S.

bonus sequence against my friend Bird, who is playing Claude's burn deck.

the board mid-chain: Every Soul Aflame, Set Your Heart Alight, and two Stoke on the stack; Ashka down to 8 health — Bird casts a bunch of mana generation, plus multiple of this Stoke card which effectively multiplies the mana!

the sources panel showing stacked FFF sources — 15 Fire mana — Look at all that mana! 15! (I had Claude add the additional Fs to sources when Stoke is used, to honor this moment)

the stack loaded with Phoenix Surge and Apotheosis of Fire plus four storm copies, all targeting me — Phoenix Surge (big burn)! Apotheosis of Fire (storm!)

my answer: the stack full of Count Your Blessings storm copies, Aegis of Dawn in play, surviving at 14 health — Unfortunately my Aegis of Dawn reduced 1 damage from each incoming spell. And I was able to counterspell the Phoenix Surge. And then I had a storm heal of my own. Bless up!