Trine was a 2009 cooperative platformer game by Frozenbyte that I played on the PC. Unlike Super Mario Bros. (also a platformer), there is more than one hero. Each hero plays completely different from the others. Not only that, each level requires the skills of multiple heroes to complete. Therefore, in single player you can switch at will to any of the heroes. Each hero has their own health and magic bars. If one hero dies, you can’t pick him or her again until you get to a save checkpoint. In cooperative mode, each player controls a different hero with no switching.
What’s great about this game is that there are unique strategies for solo mode and cooperative mode. For example, the wizard can summon a block out of thin air. The thief can then stand on that block, and the wizard can use his magic to move the block with the thief over a spike pit. In single player, you can’t control two heroes at once, so that strategy doesn’t work. Instead, maybe you have to find a wooden beam for the thief to latch onto or stack several objects in the spike pit with the wizard to jump on. The level layout is exactly the same, but you have to do different things depending on the game mode. This meant cooperative mode was generally easier than solo mode.
The graphics and sound for its time weren’t all that great, but the art style and themes were great. The whole game felt like a kids storybook. I was reading a fairytale. They had a nice narrator that would flip through pages of the book. When the narrator got to a certain point, the level would start, and I could play out the story. Once I finished, the narrator would progress the story to the next level. It was a very unique touch. They also innovated with a good physics system. In addition to stacking objects, there were also places to manipulate water and fire.
The only downside to this game was its length. It only had 12 or 13 levels if I remember correctly. I was able to finish it in a single weekend. Collecting all the treasure took longer, but not enough to discount the few levels. However, this was an indie game. Frozenbyte probably couldn’t have done any better. The game was sold at a discount price as well, only $30 at launch (half what a normal game costs).