— A Multiplayer Arena for learning Flashcards

Tristrum Tuttle
7 min readAug 9, 2021

What is a .io game?

.io games (pronounced “dot eye oh”) are a recent form of multiplayer online game that are easy to learn, hard to master, and accessible from almost any web browser or mobile device. The name comes from the top-level domain that some early game developers found both catchy and widely available. The key ingredient of .io games is simplicity — the graphics are minimal, the mechanics are self-explanatory, and there is almost no setup required. Players can enter and leave each game at will, and don’t need any type of login or user account. Most .io games are multiplayer, with game lobbies holding anywhere between 1 and 100 players. Beyond these core similarities, .io games vary dramatically and cover many different genres — from tower defense to racing to social deduction.

I believe .io games have massive potential as learning tools. They have very simple controls and are mobile-friendly, which makes them viable for students with no home computer and/or bad internet connection. The simple gameplay and graphics make set-up quick and painless, reserving more time for actually interacting with the curriculum. The multiplayer aspect forces students to practice teamwork, communication and conflict resolution.

In order to evaluate the potential benefits of .io games as educational tools, I played dozens of .io games across several genres. I played some classic .io games, like, and I tried out .io games that clone existing games, like (Rocket League), (Tetris) and I even tried some first-person shooter games (spoiler — they were not very educational) zombie games, tower defense games, and more. Lets take a look at the potential for teaching in some existing .io games:

Strategic .io Games

Thinking logically in

I love strategy board games, like Chess and Risk, so I was happy to discover many .io strategy games that were challenging and competitive! Strategy games force players to weigh costs and benefits before making decisions that will determine the outcome of the game. These skills are invaluable in the real world, and applicable across many different areas of study. Strategy games help students build critical thinking skills, and encourage students to practice planning and deductive reasoning. is a .io game that forces players to make super quick decisions using limited information from their view of the grid-like arena. Players compete to control blocks of land, and make moves to take over new territory. When two armies collide, the larger wins, forcing players to estimate their army’s size and predict their opponents’ next steps with only one second between each turn. It took me awhile to get the hang of this game, but I really enjoyed how competitive and fast-paced the games were. I learned a lot watching replays of games played by more experienced players, including some initial strategies to stay alive.

Informative .io Games

Getting eaten in

A big part of education is learning about the world, history, and other social sciences. Through gamification, studying mundane subjects can become a self-guided journey that students find enjoyable and effortless.

In you become an aquatic animal and explore several different biomes, interacting with the environment and other players to “evolve” into a new animal periodically. Even though this game is kind of ridiculous, you do get to learn about different species and the biomes they inhabit. Even the most knowledgable animal lovers may learn something new navigating the waters as an Olm or Lamprey. Monica and I played this game for a while and enjoyed trying to meet up while strategically evolving to survive in each habitat.

Collaborative .io Games

Players help each other in

.io games can turn learning into a collaborative, social experience. Even though we tend to think of education in terms of core subject areas, like math and reading, a big part of education is learning to work together with others. There is a lot of evidence that Social-Emotional Learning (SEL) is highly correlated with other measures of academic success, and skills like relationship management and social awareness are associated with positive outcomes in many facets of life. is a simple teamwork-driven game in which players attempt to navigate a field of moving obstacles to reach the end of each level. When a player hits an obstacle, they are frozen for a period of time, during which another player must tag them to unfreeze them (otherwise the frozen player will be forced to restart from level 1). This game encourages players to work together and help each other get to the next level. Even though the server was a bit laggy, I really enjoyed playing this game with Monica and trying to beat all 20 levels.

Artistic .io Games

Artistic talents on showcase in

Some .io games require students to create, build and express themselves through mediums like online sketchpads or editable worlds. These games push students to think outside the box and practice digital design skills, which are becoming increasingly relevant in the age of computers. is a fun Pictionary-like game where each player takes a turn drawing a picture, while others try to guess the initial drawing prompt. Players may have to get creative to draw some prompts, like “Internet” or “morning.” The drawer needs to balance accuracy with speed, so that other players can guess their picture before time runs out. This game is great for players of all ages, and I still play occasionally with friends and co-workers.

Making my own educational .io game

I found a bunch of great .io games that have educational aspects, but there aren’t many .io games specifically developed as educational tools. In order to test the potential of .io games as teaching instruments, I decided to create my own .io game with an educational twist. My game,, seeks to apply the .io game format to the fun, exciting, definitely educational task of memorizing flashcards. is a game where players can upload their own set of flashcards and practice them while driving a ship through a multiplayer battle arena. Players collect cards and match them, gaining points for each matched pair. When two players collide, the player with more flashcard points eats the player with fewer points. I think has potential as a gamified flashcard app for many reasons: it is easy to play with friends, it’s flexible to any schedule, and it turns a routine study chore into an engaging and competitive experience. Try it out at!

I ran an experiment comparing to a standard flash card website (Quizlet) to see which was more effective.

Hypothesis: CardBlast will be as effective at teaching flashcards as more traditional methods, like Quizlet.

Experiment: Myself and four friends studied a set of 10 flashcards for five minutes using Quizlet, then studied a different set of 10 flashcards using CardBlast for five minutes. The flashcard sets we used consisted of Hindi animal names, which none of us were familiar with beforehand. After each five minute study session, we took a quiz on the flashcards and recorded the results.


Alas, my hypothesis is incorrect — CardBlast struggled to hold up against Quizlet. All five of us scored way better after five minutes of practice on Quizlet than on This experiment was definitely not perfect — I used a pretty small sample size, and my friends have developed some good tricks for memorizing traditional flashcards. But CardBlast is definitely not an ideal alternative to other flashcard tools.

CardBlast has a few innate problems. There is no penalty for concentrating more on the “game” aspects, like driving your ship around and trying to eat other players, than the “learning” aspects. It also takes some time to find a new card and navigate to its match, resulting in fewer repetitions of each pair. I had initially tried to balance this by adding a hot/warmer/cold type indicator bar to help guide players to their next card, but it is still less efficient than a normal set of flashcards.

I am still super excited about CardBlast and think it has a lot of potential as a fun, engaging way to help motivate students to study flashcards. I am exploring new game mechanics to help balance the learning and gameplay aspects, and looking for ways to increase the number of reps players get with each flashcard pair. Hopefully CardBlast 2.0 will do a bit better against Quizlet in the head-to-head face off!

How I built

I built CardBlast with JavaScript, specifically Node.js,, and HTML5 Canvas methods following Victor Zhou’s tutorial. I am hosting the CardBlast server on an Amazon EC2 instance.

Check it out on GitHub!

Also, try it out at!

Special thanks to my girlfriend Monica for proof-reading and being so supportive! Huge thanks to my friends Hunter, Matt O, Ben and Matt L for providing experimental data, to Siegrid for helping develop my flashcard sets, and to all my other friends and relatives that play tested the game during development. Also, big shout out to Victor Zhou for the awesome tutorial and starter code.