IdleOn

IdleOn —originally called Legends of IdleOn— is a cartoonish 2D idle MMO built almost single-handedly by developer LavaFlame2. Its defining idea is as simple as it is addictive: your characters keep progressing even when the game is closed, mining, fishing, cooking and slaying monsters while you're away. More than a classic MMORPG, it's an incremental game wearing an MMO costume, where the 'massively multiplayer' part lives in the community, events and leaderboards rather than in shared adventuring. Its official site and Steam page are the best places to start.

Instead of embodying a single protagonist, you run an account of up to eleven characters from different classes, all grinding in parallel. Much of the meta is about splitting them wisely between combat and the dozens of non-combat skills —mining, fishing, alchemy, cooking and many more— so the whole account climbs evenly. Progression is vast and deliberately long-haul: seven worlds, daily bosses, collectibles, minigames and systems that unlock over months or even years. This isn't a game you finish in a weekend.

IdleOn is completely free to play: every class, map, skill, world and boss is available without paying, and there's no paid DLC. Monetization runs through a gem shop, where gems are bought with real money but can also be earned by playing with a bit of consistency. Gems grant quality-of-life boosts, speed up progress and unlock pets and cosmetics, without walling off essential content behind a paywall. You can play on PC, browser, Android and iOS —via Steam and Google Play— using a single IdleOn account that syncs your progress across platforms.

The game is alive and in active development, with LavaFlame2 running it single-handedly and frequent patches, on a scale of weeks. It left Early Access with its 1.0 version on Steam in late 2025, after closing out World 6 and paving the way to World 7, complete with new maps and skills. On Steam it holds mostly positive reviews —though the most recent ones have been a touch cooler— and on mobile it keeps a high rating with hundreds of thousands of reviews. Behind it all is a large, very active community on Discord, with the developer engaging directly.

If you're after a years-long game to dip into —the kind you open for a few minutes each day to manage your account and watch it grow almost on its own— IdleOn is hard to beat: deep, generous with its free version and packed with content for the long haul. On the other hand, if you can't stand menus, micromanagement and idle grind, or you're expecting a persistent-world MMORPG with shared adventuring, it will likely wear you down. It's a huge incremental that's honest about what it is: go in knowing that, and it can hook you for a very long time.