In December 2017, the blockchain based CryptoKitties video game became so popular that it congested the Ethereum network, causing it to reach an all-time high in transactions. In some cases, people reportedly paid more than $100,000 for a CryptoKitty non-fungible token, or NFT. By March 2018, CryptoKitties had been spun off as an independent company that received over $12 million in venture capital. Unfortunately, since that time the number of users trading CryptoKitties has declined rapidly in concert with the sharp fall in the value of Ether.

Why was CryptoKitties able to build so much initial momentum? It’s developers effectively used gamification techniques to increase the popularity of their product. By allowing users to breed existing CryptoKitties to create new ones, users developed an attachment to their new CryptoKitties since it was a product of their own creative efforts. This unique dynamic also allowed CryptoKitties to develop into a digital playground for researchers in genetics, machine learning, and game theory. In addition, like the Beanie Babies that came before them, the scarcity of CryptoKitties and the uniqueness of each one caused their price to rise very quickly.

Blockchain projects, particularly those using NFTs, can learn a lot from gaming products aside from CryptoKitties too. For example, let’s consider the popular card game Seisen Cerberus, developed by Japan’s GREE Inc. Based on characters from a popular anime series, the game became so popular that the strongest game cards were selling for over $5,000. The success of the game even led 20% of the game’s users to pay for additional features (as compared to 5% of paying users for most freemium games). To build this obsessive fanbase, GREE leveraged their users’ desire for closure with a mechanism called a “Complete Gacha”. Gachas are round toy capsules sold in Japan that cost a few US dollars. Children buy Gachas without knowing what toy is inside until they open the capsule. GREE used the same concept by having players pay to receive a card in the Cerberus game without knowing which card they will receive until they pay. Once players collect a full set of a given type of card, they receive another special and rare card. Before they knew it, people were spending a lot of money buying the Gacha cards to complete their set and receive the rare card.

Why was this so effective? People wanted to complete their collection in order to feel a sense of closure. When something is interrupted, our brains crave the completeness of seeing it finished. It’s like that Seinfeld episode when Elaine wanted to finish her sandwich stamp card — even when she didn’t like the sandwiches in the first place!

Marketing professor Robert Cialdini writes about this in his book Pre-suasion: people have a psychological need for closure, and not having that closure drives them to seek it out. This is true of our unfinished stories, unanswered questions, unresolved problems and unachieved goals — and of our incomplete collections of Ganchas. In the case of the Seisen Cerberus game, people began spending inordinate amounts of money to complete their set. It even got to a point where the Seisen Cerberus game was banned for illegally altering the probability of getting the last required Gancha to an amount lower than it should be. Surprisingly, instead of turning people off the game, the disproportionate difficulty of obtaining the last Gancha made people spend even more just to finally obtain it — that’s how high their need for this closure was.

CryptoKitties has shown that giving users a personal stake in the creation of a NFT makes them more attached to them and more likely to value them highly. The Seisen Cerberus game in Japan showed that playing on people’s desire for closure and completeness can incentivize them to pursue new collectibles like NFTs. In both cases, cleverly adding gamification elements has ushered greater demand for unique digital collectibles.