Evoland (iOS|Android) is an action-adventure game whose graphics and gameplay evolve through the history of RPG gaming as you progress through its levels. The game is also very self-aware as it gives humorous nods to many of the most popular RPG games in history.
Evoland ($4.99, £3.99, AU$6.49) is the first game I've seen that captures a whole genre of gaming from its roots all the way up to the modern day, and I found it incredibly nostalgic to relive those early gaming technologies. But even if you weren't around for the beginnings of RPG gaming and early graphics, Evoland makes it fun to unlock each technology as you solve puzzles to complete the game's own unique story.
Getting back to the roots
When you start the game there's just a thin strip of the world in two colors on your screen, and you can only move your character to the right. To the right is the first chest you can open, which unlocks the ability to go left. To the left is another chest that unlocks a 2D plane so you can go left, right, up, and down. You quickly realize that the chests unlock gaming technologies, so you're always on the lookout for the next one.
It's not just your movement that evolves, though. You also start the game in silence and only when you find the chest for early videogame music does the telltale digital melody start playing. Later, you'll get 16-bit color and an early form of "3D" called mode 7 (think of tilting the camera in Google Maps with a flat map).
The game continues like this, unlocking technologies as you find each chest, but you're also on a quest of your own in this rapidly changing world. You have multiple puzzles to solve on your journey and plenty of monsters to beat while the story and the technologies progress.
Another way the evolving technology makes the game fun is the way you fight monsters. In the beginning it's just a sword that lunges forward like you would see in early games such as the original Zelda. Later it switches to a turn-based mechanic as you would see in games like Pokemon and early Final Fantasy games. You'll touch an attack button, then select an enemy, and your character will launch forward to swing his sword, then return to his starting position. Even the turn-based fighting evolves as you play, going from 2D to colorful 3D with textures over time.
Later once you're past the turn-based era, you'll unlock tech that makes it so your sword swings in an arc. Even later, you'll get a combination move with a finishing slam that hits multiple enemies.