The Mario Game that Gets Harder the Better You Are
Ben Weber, a Ph.D candidate in computer science at UC Santa Cruz, has programmed a devious game using the familiar sprites and backgrounds of Super Mario World. Weber’s Infinite Adaptive Mario starts off with a level of moderate difficulty. Once you beat that, the next level gets harder, and the levels continue to get harder until you die three times in a row without completing a level, at which point it gets easier. And yes — “harder” really means “harder” here: It doesn’t take many levels before you encounter an enemy-infested mess comprised of the trickiest jumps.
One of the inputs to the system is a set of parameters which specify probabilities for specific events to occur, such as placing a gap. By modifying these probabilities, the system can create a large space of levels with varying difficulty. Infinite Adaptive Mario scales up difficulty by increasing the frequently of gaps, average size of gaps, variation of ground height, and number of enemies. Scaling up the difficulty also tends to result in a larger number of possible paths through a level. [emphasis added]
The player begins at level 50, which produces levels with a moderate degree of challenge. Upon successful completion of a level, the challenge is increased. Faster completion times result in larger increases in difficulty. Upon death, the difficulty is decreased based on the amount of progress made by the player. If the player is close to the goal upon death, then the difficulty is decreased only a small amount. A new level is generated when the player either completes a level or fails to complete a level after three deaths.
You can see in the screenshots below just how insane the game gets when you hit the highest difficulty stages: Sixteen enemies onscreen at once? Winged, horizontally moving piranha plants?
Weber has also pitted Infinite Adaptive Mario up against an AI program for completing randomly generated Mario levels: Robin Baumgarten‘s A* agent, which won 2009’s Mario AI competition. You can see in the video below (from which the two screenshots above are pulled) how that turns out:
If you’re interested in giving the game a whirl, you can download it here as a JAR. It’s still a little buggy (unless the randomly blinking Bullet Bills are intentional), but it’s still quite playable, and it does, as promised, get very very hard very fast. And it’s surprisingly addictive, in a masochistic way. Where’s Yoshi when you need him?