Every level feels fresh, assembled in a near-random fashion by the dark code that powers Spelunky—code that, incidentally, Yu made available for non-commercial use on the Spelunky website.
Like your starting complement of bombs, ropes, and health points, Spelunky's levels come in sets of four. Survive four levels of the mines and you'll reach an underground jungle full of savage new enemies and traps to surmount. Survive four levels of that and you'll face another pair of new environments, four levels apiece, before facing the final boss.
Spelunky's levels are always surpassable, but they're rarely simple; the code often places deadly traps in near-unbeatable combinations or locks valuable treasure away behind layers of stone. Sometimes these randomly-generated levels are further modified with "Level Feelings" that render them pitch black, overrun with snakes, or haunted by the undead. To survive and thrive in these conditions you have to master the game: learn exactly how high and far your character can jump, how to effectively use the bombs, ropes and special items you'll find scattered throughout the caves, and memorize the patterns of every enemy and trap you encounter. It's a bit like a classic Super Mario Bros. game, if Mario rolled into the Mushroom Kingdom packing a whip, bombs and a grappling hook.
Rise to the challenge
Like Mario, Spelunky's cast of plucky adventurers never gain experience points or permanent upgrades. They never level up; you do. Spelunky only gets easier because you as a player develop the skill and expertise to make it so, using the experience earned every time you die. It's tempting to succor new players by claiming that Spelunky is fair and balanced enough to avoid frustrating you, but it's not true—you will be frustrated. You will die countless times to learn the patterns and peccadilloes of the traps and monsters that wait for you in the depths.
Stick with it, and you'll find the satisfaction of accomplishing something momentous in Spelunky—reaching a new area, unlocking a shortcut or a new character, beating the final boss—is commiserate with the time and effort required. Even better, as you dig deeper you'll discover new depths, figuratively and literally, to Spelunky's design.
Here's an example: I've been playing Spelunky irregularly since it was released in 2008, racking up almost a hundred hours played across both the PC and the Xbox 360 versions. I can brain vipers with a well-aimed stone from across the screen, dodge giant rolling boulders with aplomb, and find the secret entrance to the Black Market. Yet while playing the Vita version of Spelunky for review this weekend I discovered, to my complete surprise, that you can run through spike traps.
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