The primary feature of indie browser games which differs them out of range of other projects is a small number of developers and low development budget. They also feature unique gameplay models, that can be released only with high risks for the developer. Of course, indie projects can feature classic genres, but this type of games is much more attractive for experimentation. Still, indie games can be published and distributed by major companies; also, this label is not the equivalent of a high-quality product. Indie browser MMOs are often crowdfunded for the development, and the developers don't aim at the profits of their projects, but on the idea and gameplay. It's an opposite of the conveyor of commercial games, which provide players with the crazy amount on microtransactions, pay to win elements and overpriced cosmetic features.
Since developers are not limited in their creativity, only Indie Browser Games can provide the most unusual gameplay and plot. These games can have one the most mind-blowing mechanics and non-cliche storyline, sometimes even absurd, which rarely can be found in games made by classic developer teams. Another feature of browser indie projects is their availability: you don't have to buy a specific device to play the game, all you need is a browser with a good internet connection.