Can two designers come up with the exact same idea, entirely by accident?

Could you design a brand-new game using only a deck of classic playing cards? It's a cool idea — repurposing familiar components in an original context. But the design for the game that would become Donsol was born out of necessity, the mother of invention. A pack of cards was all the creators had on hand.

Devine Lu Linvega developed the iOS version of Donsol, a game that sees heart suits re-cast as "health potions," clubs and spades as "monsters". Starting with four cards, the player gathers health and fights enemies, making their way through an imagined dungeon space making combat calculations — the health cards versus the monsters. It's a fascinating idea.

The only problem is that completely unbeknownst to Linvega, someone had already made it.

Donsol is almost exactly like Zach Gage's Scoundrel. Was malicious copying afoot, or is it just that there's only so much you can do with a deck of cards after all?

Linvega met John Eternal, who works for Sony, on the Train Jam earlier this year. Game developers buy tickets to buy the cross-country train to San Francisco, with the annual Game Developers Conference as the final destination. On the trip, they form tiny teams and make small games — in game development, the "jam" environment posits that with unique settings and specific constraints, collaborative new ideas and relationships can form.

According to Linvega, Eternal turned up for the jam, but left his power supply behind. "Stuck on a train for 52 hours, he had to… improvise," Linvega tells me. "He had a deck of cards, and he made this game."

Linvega and his colleague enjoyed the result so much that Linvega volunteered to make a score-keeping app for Donsol on iOS. He ended up helping iterate on the design and contributing his stark, distinctive art style to the cards.

When Zach Gage found out about Donsol, it was an unsettling experience: The game was "basically identical" to Scoundrel, a game the prolific designer had created in 2011 along with Kurt Bieg. The similarities were so strong Gage found it hard to believe neither Linvega, whom he knew, and Eternal, whom he didn't, had seen Scoundrel before.

Cloning, particularly on the App Store, is a crippling problem for game developers today. Releasing a high-quality game — one that takes financial investment, time and design innovation to create — on a mobile marketplace for even a tiny fee usually means a clone artist will quickly knock off the game wholesale and offer their nearly identical version for free.

When a game is popular, this means a cloner can siphon massive amounts of revenue from the original designer and enrich themselves via ads in the free app. Your average casual game player isn't concerned with the difference between a free puzzle and the "authentic" original — if they're aware of an original at all.

The highest-profile case of this phenomenon recently is probably the case of Threes, a hooky number-puzzle that had its thunder stolen by 1024, a clone whose market penetration seems to have wildly outperformed the original. Mainstream outlets like CNBC, no better informed than your average consumer about the games market, even breathlessly celebrated the overnight success of 2048 — a game that was itself a clone of a clone.

Apple has shown no inclination to curate or prevent clones on its platform, as it has no real financial incentive to address the issue. As much as the company has relied on games to showcase the appeal of its iPhone and iPad, at the end of the day it's not interested in becoming a "games platform". Even though smartphones and tablets could become the next great ecosystem of play — the devices are virtually ubiquitous in the Western world — saturation on the App Store and the prevalence of clones choking the financial viability of truly new, high-quality ideas on mobile marketplaces continue to inhibit game developers from investing meaningfully in those spaces.

But Scoundrel, while played heavily for a time in the small-world game design community (where it would certainly have the opportunity to be seen by and to influence many designers) never actually saw digital release, and today lives mainly as a ruleset; there's no edition on mobile marketplaces at all, let alone one that sits beside Donsol. In fact, Linvega tells me, he and John Eternal were more worried about being compared to a different card battle game called Card Crawl (which also has some traits in common with Scoundrel, naturally).

"It's very hard for me to imagine [Devine Lu Linvega] cloning someone, with his track record of originality," a bewildered Gage admits. As a massive fan of Linvega's work myself (read a profile I did of him here), I feel the same: The enigmatic creator hardly seems interested in populist trends, or even in media coverage.

He has a diverse portfolio of small works unified by a minimalist black-and-white design sensibility: A language-learning app, a strange alt keyboard, an alien diplomacy game involving bodily fluids and uncomfortable intimacy. My favorite Linvega project, Paradise, is a living universe of text, descriptions of objects nesting within one another, and any user can add to it. It's easy to see why he'd be attracted to Donsol's simplicity, but hard to believe he'd ever be interested in emulating anyone else for personal gain.

Both Linvega and Eternal say they never saw or heard of Scoundrel before. Eternal said the inspiration for Donsol was nothing more specific than Dungeons and Dragons; for Linvega's part, he said it was his decision to distill Eternal's suggested five-card "worlds" down into Scoundrel-like four-card ones. Both creators were more than happy to offer Gage a credit on their App Store game — it seems as though the striking similarities were nothing more than a mistake.

Designer and teacher Naomi Clark is one of the greatest minds of the New York City game scene. I asked her how possible it is, how common it is, for game designers simply to have simultaneous ideas. Maybe there's a limit, I thought, on how many things can optimally be done with certain components.

Game mechanics are just sets of possibilities: for relationships between things, interactions between players, how nodes of an ecosystem can interact, she tells me. "I tend to think of game mechanics as if they're things that are already out there in the world, independent of individual human beings — that we're discovering something, rather than coming up with it all by ourselves," she says.

"This explains why two people creating a game can stumble across the same mechanic, the same interaction and effect, even if they've never met, never played each other's games," Clark continues. She's even had it happen to her.

"It used to make me gnash my teeth, that someone else had also come across the idea that I was so proud of devising, and had beaten me to announcing or launching a game," she says. "Over time, I've gotten much less attached to the feeling that any game mechanic could truly be 'my idea'."

Clark is currently re-imagining cyberpunk dystopia card game Netrunner as a Victorian drama of manners (for fun, not profit): "A game is a lot more than a mechanic, and if anything could end up being 'mine', it'd be how I worked with a fundamental idea and molded other parts of a game to accompany it," she says.

"The recent lawsuit over 'Blurred Lines' and its similarity to Marvin Gaye's 'Got to Give it Up' surprised many music-industry observers exactly because the conventional wisdom about songs is that only the lyrics and top-line melodies can be "cloned" or copyrighted," says Clark. "Other aspects of a song, from the structure of the song's phrases to 'classic' rhythm lines and hooks, are shared in common between many songs."

As a relatively young medium that often courts very focused and intense fans — the same people who go on to become creators — game development is fairly insular relative to other media, and the pool of influences tends to be more limited. That's why the idea of innovation is so widely worshiped in the design community, often invested with inappropriate primacy.

"In the case of the dungeon-crawling solitaire games, the creator of Card Crawl seems to have deliberately taken inspiration from Scoundrel, while the creator of Donsol describes the similarity as accidental," says Clark. "Both are believable, not just because we can independently discover the same things, but because we're in a period when there's more and more overlap between digital game designers and board & card game designers."

"The fact that all three games are presented as dungeon-crawling roguelikes definitely isn't just a coincidence — it's also born from a shared cultural heritage," Clark adds.

"Still," Linvega tells me, "it's the kind of mistake you can only do once in your career."