At NYC Media Lab and New Tech City’s gaming edition of Geek of the Month, hosted on June 5 at General Assembly, one of the audience members asked: what makes a game a success?

“It has to have birds,” joked Colleen Macklin, a game designer who is also a professor at Parsons The New School for Design in New York City and Director of Parsons’ PETLab.

“Or candy,” added New Tech City’s Manoush Zomorodi.

Kidding aside, it’s a hard question to put your finger on, said Macklin. “A lot of it is how the games make you feel. A lot of it is about context. There’s also flow; how do you create enough of a challenge — not too much, not too little — to keep people engaged?”

In other words: there are a lot of different ways to create a successful game. And to explore the diversity of ways that games can engage, challenge, and delight, the indie game scene is an excellent place to start. From unconventional methods of play to thoughtful explorations of topics like immigration and gender transformation, indie games challenge the common notion of what constitutes a game.

To give a sampling of the indie game scene, Colleen Macklin shared fifteen of her favorite titles:

1. Journey

Developed by thatgamecompany in 2012, Journey is an online adventure game that solves the problem of player interaction in a game. Devoid of text and voice chat, players must interact with each other only using abstract sounds, symbols, and body language. “Sometimes less communication is more,” says Macklin.

2. Minecraft

One of the best-known indie games, Markus Persson’s Minecraft is like “modern-day Legos,” says Macklin.

3. Dys4ia

Deeply personal, Dys4ia is a free online autobiographical game about the game designer Anna Anthropy’s experience transitioning during hormone replacement therapy. Anthropy uses vintage gaming tropes to tell her story. Macklin says, “It’s a new form of storytelling, and I think it’s really powerful.”

4. Crystal Warrior Ke$ha

Created by game designer Porpentine, Crystal Warrior Ke$ha uses Twine, a free open-source tool for text-based games.

5. Unmanned

Unmanned, developed by Molleindustria, is notable in its choice of topic: the life of a drone pilot. Unlike mainstream games, Unmanned is part of a scene in indie gaming that explores how to communicate complex ideas and challenge preconceptions through games.

6. Papers, Please

Also in this scene is Papers, Please by Lucas Pope, which puts you in the shoes of a borders clerk who decides who gets to cross the border—and who doesn’t—by scrutinizing their paperwork.

7. Kentucky Route Zero

“This is the new Twin Peaks,” in game form. In addition to visuals so beautiful that “they’ll make you cry,” Kentucky Route Zero by Cardboard Computer is interesting for its structure: like a television show, the game is segmented into episodes.

8. Spaceteam

Self-described as a “cooperative shouting game for phones and tablets,” Spaceteam by Sleeping Beast Games requires that players work as a team using verbal commands to collectively control a spaceship.

9. Tiny Games

Another example of a game that puts the play outside the device, Tiny Games by Hide & Seek consists of hundreds of little contextual games that can be played in the physical world. Macklin was a guest designer on this project.

10. Proteus

Proteus, a 3D environmental game from Ed Key and David Kanaga, operates similarly to most first person-based games. What’s interesting about this game, says Macklin, is that it raised questions in the game scene about what constitutes a game.

“You just wander around and listen in this game,” she says. “It’s pretty profound and beautiful.”

11. Renga

Renga, by wallFour, is played by up to 100 players in a theater with laser points. Players must coordinate their actions in order to advance to the next level. Renga borrows from the technology produced by the Graffiti Research Lab, which developed a way to use laser pointers and computer vision to project onto the side of buildings.

12. Johann Sebastian Joust

Johann Sebastian Joust provokes the question: “what is a video game?” Developed by Die Gute Fabrik is a game that uses PlayStation Move controllers, sound, and nothing else. Players try to keep their Move controllers steady while attempting to jostle their opponents’ controllers.

“It really harkens back to playground games, like tag,” says Macklin.

13. Killer Queen

What’s interesting about this project from Josh DeBonis and Nikita Mikros, says Macklin, is its origins; Killer Queen began as a physical game for the Come Out & Play Festival, eventually making a transmedia jump into a multi-player arcade game.

14 & 15. Starry Heavens & Interference

“When we think about non-digital games, the most exciting work out there comes from Eric Zimmerman and Nathalie Pozzi,” says Macklin.

They create “incredibly beautiful” physical installations like Starry Heavens and Interference, each one subverting what we usually think of when we think of games.