Pity at 90 pulls: the dark UX of gacha games

How gacha games use dark UX: virtual currencies, pity systems, near-misses and limited banners, what regulators did, and how to design better.

The word comes from a toy machine.

In Japan, a gachapon is a capsule vending machine. You put in a coin, turn the handle (gacha), and a plastic capsule drops out (pon). Inside is one toy from a series, and you don't know which one until you open it. It's a small, honest gamble: the price is written on the machine, the coin leaves your hand, and you can see how many capsules are left.

Gacha games kept the capsule and took away almost everything else.

When collecting became illegal

The first warning came in 2012. Japanese mobile games had added a twist called kompu gacha, short for "complete gacha": collect every item in a set of random pulls and you unlock an ultra-rare prize. The last missing piece of a set is, by design, the hardest to get, and players kept paying to find it. Press coverage at the time mentioned a middle school boy who spent around $5,000 in a single month.

In May 2012, Japan's Consumer Affairs Agency declared complete gacha illegal under an existing law against misleading premiums, and the big publishers dropped it within weeks (Game Developer has the background).

The mechanic disappeared. The industry around it didn't. It just moved the pressure somewhere less visible.

What makes UX "dark"

The designer Harry Brignull coined the term dark patterns in 2010 for interfaces that trick people into doing things they didn't mean to do, and still catalogues them at deceptive.design. In 2018, Colin Gray and his colleagues sorted them into five strategies: nagging, obstruction, sneaking, interface interference and forced action.

Games got their own version. In 2013, José Zagal, Staffan Björk and Chris Lewis described dark patterns in game design as choices made on purpose to create experiences that go against the player's interest, and grouped them by what they take from you: your time, your money or your relationships.

A gacha game can use all three in a single screen. Let's open one.

The anatomy of a gacha pull

The currency fog

You never pay for a pull in euros or dollars. In Genshin Impact, for example, real money buys one currency, which converts into another, which buys the item you spend on a wish. One wish costs 160 Primogems. Quick: how much is that in money?

That pause is the design. Every layer of currency puts a little more distance between the tap and the bank account, and bundle sizes often don't line up with what things cost, so there's almost always some currency left over, nudging you toward the next purchase.

In January 2025, the US Federal Trade Commission settled with the publisher of Genshin Impact for $20 million. Among its allegations: the game misled players about the odds of winning five-star prizes and what it would cost to win them, and its multi-tier currency made those costs hard to judge, especially for children and teenagers. Part of the order: loot boxes can no longer be sold only for virtual currency without the option to pay in dollars directly.

"Pity" is a progress bar

Most gacha games guarantee a top-rarity reward after a certain number of failed pulls. In Genshin Impact's character banner, that guarantee lands by the 90th pull. The players' own word for it is pity.

It sounds merciful. It works like a progress bar. Each failed pull moves you closer to the guarantee, and the closer you get, the harder it is to stop. Research on loyalty cards found exactly this: in a 2006 study of coffee shop customers, Ran Kivetz, Oleg Urminsky and Yuhuang Zheng found that people buy more often as they get closer to a reward. At pull 70, walking away feels like throwing away the 70 pulls before it.

Then comes the 50/50. On many banners, the guaranteed five-star has a 50% chance of being the featured character. If you lose it, the next guarantee is the right one, and the progress bar starts again from zero.

The almost-win

A pull isn't shown as a result. It's shown as a reveal: a shooting star, a colour that hints at the rarity before you see what you got. The suspense is built into the animation.

Gambling research shows why the misses matter as much as the wins. In a 2009 brain imaging study, Luke Clark and his colleagues found that near-misses on a slot machine felt less pleasant than clear losses, yet increased people's desire to keep playing, and activated reward areas of the brain that also respond to real wins. My reading, and it's an interpretation rather than a finding from that study: losing a 50/50 is a near-miss by design. You did get a five-star. Just not the one you wanted.

The clock

Featured characters come on limited-time banners, usually for a few weeks. Daily login rewards and daily quests make you come back on the game's schedule. Zagal and his colleagues called this playing by appointment. Scarcity does the selling: if you don't pull now, the character might not come back for months.

The button in the wrong place

Sometimes, dark UX doesn't need psychology at all. Just a button where your thumb already is. In 2022, the FTC said that Fortnite's publisher, Epic Games, used dark patterns that led players into unwanted purchases: according to the regulator, players could be charged while trying to wake the game from sleep mode, during a loading screen, or by pressing a nearby button while previewing an item. Epic agreed to pay $245 million in refunds, the largest refund the FTC has ever obtained in a gaming case.

Are loot boxes gambling? What the research says

The link to gambling is now well documented. In a 2018 survey of 7,422 gamers, David Zendle and Paul Cairns found that the more people spent on loot boxes, the more severe their problem gambling tended to be. The authors are careful about direction: loot boxes might lead people toward problem gambling, or people who already gamble might be drawn to loot boxes. Either way, it's a pattern worth designing against.

Regulators don't agree on what to do. In 2018, Belgium's Gaming Commission ruled that paid loot boxes in several major games broke its gambling law. In the Netherlands, a similar decision against FIFA was overturned by the country's highest administrative court in 2022. Apple's App Store took a narrower route: any app selling randomised items has to disclose the odds of each type of item before purchase.

Odds on a screen help. But a percentage tells you less than you'd think when you're three currencies away from your money and 70 pulls into a progress bar.

A collection without the casino

I've designed a collection mechanic myself, in a concept for the Meguro Parasitological Museum in Tokyo: visitors find hidden parasite specimens while reading the exhibits and drag them into a specimen box. Same urge to collect as a gacha game. Every other choice went the other way, and comparing the two shows how many separate decisions dark UX is made of.

• Nothing is random. Every specimen is on a page, findable by reading. You never pull for it.
• Nothing is for sale. There's no currency, so there's nothing to convert and nothing left over.
• No clock. No limited banner, no daily login, no countdown. You can stop halfway, and nothing pushes you to come back tomorrow.
• No comparison. Progress is private. Nobody sees whose box is fuller.
• One celebration. Sound and animation stay calm on every catch. The only fanfare plays once, when the box is complete. If every pull is a firework, the fireworks are what you end up chasing.

None of that makes a collection less fun. It makes it a game you can leave.

Ethical monetisation: rules you won't be ashamed of

• Show the real price. If something costs money, show the amount in money at the moment of purchase, not only in crystals or gems.
• Write odds in plain words. "About 1 in 170" means more to a person than "0.6%".
• Keep purchase buttons away from everything else. Never put a paid action where people tap to wake, skip, preview or close.
• Let progress be earned, not rolled. If the thing people want most is behind chance, the chance is your product.
• Don't put a countdown on something you sell. Time pressure plus payment is the oldest trick in the casino.
• Make stopping free. If leaving costs players their progress, you've built a reason to keep paying, not a reason to keep playing.
• Run the gachapon test. Imagine your system as a real capsule machine, with the price written on the front. Would people still feel fine putting a coin in?

Keep the coin visible

The capsule machine in a Tokyo arcade is a gamble too. But you hold the coin, you see the price, and when your pocket is empty, you stop.

That's the whole difference. Good game design can keep the surprise of the capsule. It just has to let you see the coin.