Spelunker was originally published on the Atari 8-bit and Commodore 64 computers. Similar to Pitfall II: The Lost Caverns, it puts you in the role of the titular unnamed spelunker, who seeks treasure in the pits of an enormous cavern. There is a time limit, as indicated by the amount of oxygen remaining at the top of the screen. The only way to fend off ghosts is by blowing your air gun at them, further lessening your supply. The ghosts also appear randomly, usually at inopportune times, and can greatly screw you over. The game seems to present some kind of non-linearity by letting you pick different shafts at the beginning of the game, but in reality you'll usually need to explore and gather almost everything, including air tanks to refill your oxygen, bombs to destroy rocks, flares to distract bats and colored keys to unlock various doors. There are, of course, plenty of score-giving treasures to find too.

Every single step is dangerous - the hero must avoid pits, avoid deadly bat droppings, jump over steam geysers and even contend with the ghosts of his fallen predecessors. But the deadliest obstacle of all is the absurdly tricky control scheme. You can only survive a fall about roughly the height of your character - any farther and you'll simply fizzle out of existence and respawn at a nearby checkpoint. It's all incredibly sudden, especially since you don't even get the joy of seeing your little man fall to the ground. This is only the beginning of the problems, because there are numerous quirks involving character movement. Perhaps it is years upon years of playing side-scrolling platformers, but usually you can walk off a horizontal surface and expect the momentum to carry you at least a little bit, allowing you to potentially reach the next platform. Not so in Spelunker - you drop like a rock if there's so much as a pixel of space between the floors, and it's a lesson you learn almost immediately as you step off the elevator at the outset.

Another issue is the tiny piles of rubble which somehow causes you to leap automatically in the opposite direction, usually to your death. Or the bombs, which are needed to destroy walls and can kill you if you're too close when it explodes, but gives absolutely no indication of the safety radius. Or the low ceilings which can totally screw up your jumps. And the most frustrating of all of these is how to deal with the many ropes hanging in the caverns. You'll usually need to jump back and forth between them, but you have to press a direction and the jump button at the precise same time, or else your character will interpret this as a command to walk off the rope and die almost immediately. It is also nearly impossible to tell how far you can crawl down a rope before you drop, which will usually result in yet another death.

When the Atari and Commodore 64 versions of Spelunker were initially released in 1984, it was applauded for its seemingly large game world. After all, most platformers only scrolled from left to right - Spelunker does too, but spawns a great vertical depth. Although it's technically divided into levels, they also transition smoothly from one to the next, giving the appearance of one huge game world. (Certain computer versions do stop to load, however.) While technically not all that large - a perfect player can see it all in less than ten minutes - it sure feels huge.

While the original versions maintained some level of popularity, Spelunker took on a life of its own when it was ported to the Famicom. The original game had some fairly restrictive rulesets, but this version makes them way, way worse. The distance you can survive falls is even shorter, making it all too easy for even the most innocuous jumps end in death. The controls are even touchier, especially when it comes to jumping off ropes, resulting in even more deaths.

Some might criticize the game for not developing levels in accordance with the limitations of the control scheme, as if it were simply an oversight. The truth may be far more cynical, in that the stages seem to be deliberately created to frustrate and infuriate anyone who would ever dare to play it. Like any classically difficult game, there's a certain compulsion to overcome its harsh obstacles. It is possible to beat it, although it require strict adherence to the control scheme and near flawless controller inputs. It is possible to enjoy the game unironically, as like so many aggressively difficult games, it has developed something of a cult following amongst the hardcore set, who see its awful control scheme as a challenege to overcome.

As for other differences, the level layout is similar, although the initial elevator shaft does not go down as far, and the Japanese versions do not need to stop to load between stages. The original Atari 8-bit version opened a part of Pictures at an Exhibition by Modest Mussorgsky, but was changed in all other versions, including the later re-releases, to a much more dramatic, foreboding song. The computer versions are all silent during gameplay, except for the sound effects, while the NES/FC version adds a background song. It's short and simultaneously catchy and irritating. It's buried its way strongly enough into the Japanese retro culture consciousness that you can find many remixes on official and doujin music CDs. Repeated plays in the NES/FC version also unlocks increasingly difficult quests, using the same layout but different color palettes and various aspects becoming more difficult, such as making the keys invisible, although keeping them in the same location.

When it was released on the NES in 1987, not many American games paid attention to it, and the few that did play it did not speak of it kindly. Things were technically not much different in Japan - it did not have some mystical characteristic that only the Japanese could appreciate - but for whatever reasons it sold quite well. It quickly gained reputation as a "kusoge", reviled for its sloppy controls but simultaneously admired for how hilariously difficult it was. The reputation of the hero even created its own slang terminology, commonly used in sports. (スペ体質), "Supe taishitsu" or "Constitution of a Spelunker" means someone who gets injured very easily, with the verb "superu" meaning to be crucially injured due to something extremely minor, both referencing the fragility of the game's hero. Baseball fans have applied this Fukuoka SoftBank Hawks player Hitoshi Tamura, with the term being a "Tamura Superu", due to his ridiculously long list of illnesses and injuries.

A few months before the home release, Irem also developed a version of Spelunker for the arcades. While the basic concept and gameplay is the same, it's been drastically reworked to focus more on action and less on precise platforming. For starters, the gun was rarely used in the original versions, only to scare off ghosts. Now, it's a standard projectile weapon, and the stages are filled with enemies to be killed. Bats don't even drop guano anyway - they simply swoop to attack. Falling no longer kills you, even if you drop several stories - it just momentarily stuns you, then you're on your way. The level layout is similar to the FC/NES version, and it also requires finding keys for the colored doors, but they're not quite identical. There's a greater focus on uncovering hidden passages, although most are easy to find.

The graphics are technically far better than any of the others, although the hero has a cartoonishly large head and an equally silly bright red nose. The graphics are much brighter, and along with the background - the original game was stark black - it's a much less foreboding game in general, especially when considering how much easier it is than its brethren. It creates an interesting paradox though - while technically a "better" game, in removing what made it so unique, the arcade Spelunker doesn't have a whole lot to set it apart, and ends up merely as another action-platformer, just one that happens to take place in a cave.

This arcade only sequel is much like the first, although unlike any of the other iterations, it's an entirely new cave that's not based on any previous designs. The color scheme is now a murky green, and most of the enemies are new. Further additions include scuba tanks, for some brief swimming segments, and a skateboard, the usage of which is as stupid as it sounds. There are a few new landmarks, like a wrecked ship, several dinosaur bones, and even a large, apparently still living brontosaurus.

There's some minor changes to the way the Energy meter works - instead of dying in a single hit, it simply drains the meter. However, while falling in the first game was basically harmless, here it will drain your Energy as well, potentially killing you outright if you fall too far. The end of each stage is marked with a brief cinema of the hero walking into a chamber to pick him a new treasure. The final treasure is a princess, granted to you as a reward for conquering the caves, which seems a little bit more sexist than usual. There's a greater emphasis on hidden stuff this time around, but functionally it has the same pros and cons of the first arcade game.

Spelunker II for the Famicom is an extremely weird product. It's absolutely nothing like the original game - instead of being a straightforward action-platformer, it's an open-ended action-RPG, vaguely similar to Metroid or The Goonies II. It almost feels like a totally different game that simply had the Spelunker name attached to it due to its popularity on the Famicom. It was produced completely by Irem, without any involve from Broderbund or Tim Martin.

Although much of Spelunker II takes place in caves, you also wander around an overworld, searching for items that will unlock doors and allow you to progress. You have a life meter now, and it controls nothing like the original, with none of its quirks (although you do take a tiny bit of damage if you jump too far.) Like most of these types of games during the era, it's a bit easy to get lost, since there's no in-game map and little graphic variation, and no real direction either. It's also tough to map because, like The Goonies II, the overworld uses a dual layer world map for "front" and "back" planes. The action is also clumsy, as certain enemies take too many hits to kill, or attack in patterns that are extremely difficult to dodge effectively. You have only a single life, and there are no checkpoints, continues or passwords. It is comparatively shorter than others of its type - if you know exactly where to go, it can be beaten in an hour or so - but it is still quite harsh.

When you start, there are three character classes to choose: the Explorer, the Clergyman and the Esper, each with different skills. All characters have a close-combat and a projectile weapon, with the projectile weapon sapping health if used. At the outset, you can also stock up on supplies - rations to restore health and bombs to blow up stuff. The Explorer looks most like the hero of Spelunker and is the default character, so it might be logical to assume he's the ideal choice, but it's a trick, because he's actually the worst. The Clergymen can attack undead enemies with his default weapon, which can normally only be killed with the awkward Rosary item. The Esper can leave behind markers and teleport back to them later, making exploration infinitely quicker. The Explorer has none of these traits and his only benefit is the ability to carry more supplies into action.

By far the oddest aspect of Spelunker II is the Toku meter. "Toku" translates to "virtue", and works similar to RPGs like Ultima. Every time you kill a bad guy, you gain virtue. Every time you grab one of the hints lying around, you lose some. For the most part, it doesn't affect much of anything, unless you fall into one of the pits lying around the landscape, which, for some reason, lead straight into hell. If your virtue is high enough, you'll be tossed back into the land of the living at a minimum penalty. If it's too low, you'll be sentenced to an eternity in the underworld and lose the game. (The same thing happens if you do something particularly horrible, like killing the injured deer that you're supposed to heal.) The whole concept feels shoehorned in and really has no place in a game like this.

Disregarding the fact that Spelunker II has no real place in the series canon, fans of these type of 8-bit exploratory games may find something to like, but the core action is so troublesome that it's hard to really enjoy.

Tozai Games, who developed the remakes of Lode Runner and R-Type for the Xbox Live Arcade, also remade Spelunker for the Playstation 3 and released solely on the PSN. It was released in 2008 in Japan under the name Minna de Spelunker, but wasn't published worldwide until 2010, when it came out under the name Spelunker HD. It's more than a mere remake, because it drastically expands the concept while maintaining the core gameplay.

It's somewhat scary how closely Spelunker HD plays compares to the original. The mechanics are just as rigidly punishing as the NES game, the controls are just as stiff, and the hero is just as fragile. It even emulates the shaky animation of the main character fairly well. The only improvement is the ability to turn on "Vine Assist", which lets you hold a direction on a vine without falling off. (The same thing, strangely enough, does not apply to ladders, which you can still plummet off of if you're not careful.) At first it seems like the developers were insane to not fix any of the issues of the original game, but that would have been missing the point. As the arcade game indicated, Spelunker with "good" controls is not Spelunker - it is merely another generic platformer. As such, Tozai has an extremely solid understand of the original game.

The biggest improvement - which may seem subtle at first - is that the level design is much more accommodating. All of the original versions of Spelunker had stages which seemed designed to infuriate, but Spelunker HD has a much gentler curve. It's still quite easy to get killed, of course, but once you've mastered the particularity of the controls, it actually becomes remarkably playable. Part of this may have to do with the zoomed-in view, which has substantially larger sprites than any of the other versions of the game. You can choose between the revised HD tilesets and a retro one using a similar style to the Famicom game, and those chunky sprites blown up so large look a little strange, but it really does help make it easier to control.

The levels themselves are drastically, drastically expanded. The original game has six levels. Spelunker HD has ten areas, split into ten levels each, for a total of one hundred levels, nearly twenty times the length of the original. The first area is a cave, with a layout vaguely similar to the NES version, at least for the first few levels, but it's definitely not quite the same. The later stages take on different themes like ice levels, ruins, volcanoes, and so forth. This means many, many new obstacles and enemies compared to the original versions - the first stage alone introduces Indiana Jones-style boulders, as well as deadly spiders, which lie in wait until you're right underneath them, requiring near perfect timing to get past them. There are also numerous hidden mural pieces throughout the stages, which will slowly piece together a large picture once all of them are collected.

Until you get used to controls, Spelunker HD is still quite hard. Extra lives are numerous, thankfully. There is a save system in place, the usage of which is practically mandatory, but it's very awkwardly implemented. You can save at any point, but it dumps you back to the title screen. You can immediately reload it - it's not technically a "quicksave", so it doesn't delete this saved game - and you'll be roughly at the same spot, with the same number of lives. Essentially it forces you to make your own checkpoints. The game lets you start at the beginning of any of the 10 areas, but not any of the sub-levels. Since it can potentially take up to an hour to clear a single area, which can also be lost if you run out of lives, this save system is one of the major things that keeps the difficulty manageable.

A few other features round out Spelunker HD, including multiplayer. Four people can play on a single console and six can play online. The few songs from the original NES game are included in remixed form, as well as completely new songs for all of the new areas. The updated graphics aren't great, but are acceptable for a $10 title. The main character also has unique animations for each type of death, and the eulogy during the Game Over scene also describes your manner of death.

It's easy to see why this game stayed in Japan for so long - it's not a game that most players would "get", at least not initially, simply for how easy it is to die. But if you're familiar with the lineage - and perhaps more importantly, have the patience to deal with the control scheme - it's actually a pretty fun game that keeps in the (still frustrating, honestly) spirit of the series while greatly expanding its scope.

Japan also saw a pseudo-sequel, Minna de Spelunker Black, with more challenges.

There was a twenty two year gap between the original Famicom Spelunker and Spelunker HD, not counting the illegitimate Famicom sequel. During that time, the hero of Spelunker found infamy amongst Japanese internet memes, prompting doujin group Chinchilla Softhouse to create their own updated version in 2006. Dubbed Clannad Spelunker, it feels and plays like a true sequel, except the old spelunker guy is replaced with the girls from Key�fs visual novel/anime Clannad, abiding by the rule that every single doujin game must have a significant moe quotient.

At the outset you can pick from four girls, each with different characteristics. Nagisa can double-jump, for instance, while Kotomi is fast but weak, and Tomoyo has a strong gun and lots of health but is pretty slow. The ultimate goal is to explore the five stages of the cavern for 48 different treasures, ranging from innocuous things like bridal veils to more serious things like ancient swords. There are also numerous hidden characters to find, making this a fairly meaty game.

The basic gameplay is faithful to Spelunker, although a bit more generous. You can fall slightly farther than you could in the NES game, and it at least has the courtesy to let you hit the ground before killing you, since technically some characters can save themselves with a double jump. With all of the additional skills, it�fs smoother to play, although it�fs still pretty strict with jumping off vines and so forth. The guns work a bit differently, though - it works like the arcade game, as the heroines fire projectiles and need to line up their ghosts to kill the ghosts, instead of just facing in the general direction and firing. The ghosts (and other enemies) tend to take several hits, as well. The air meter is gone, so there is no more time limit.

Like the NES game, the goal is to explore, finds keys and unlock doors, which leads to further delving. The types of caverns include, including the standard rock cave, jungle ruins, water caverns, a volanco area, and a pyramid. At any time you can return to the entrance to save your game, although it only records the treasures and characters you've found and not your actual progress. In other words, every time you play, you�fll still need to get to the exit to unlock the next area. However, there are transporters that let you revisit any old areas, providing you don�ft exit the game completely.

The 2D graphics are decent, with a resolution at SVGA level, although obviously the bright-haired schoolgirls clash with the rest of the scenery. The newly composed music is quite catchy, although the jibber-jabbering and shrill whines of the girls get annoying quickly, and can thankfully be turned off. It strikes a good balance between being faithful to the original and fixing up some of the more frustrating elements - even slightly moreso than Spelunker HD - although the limitations of the save function ultimately hold it back.

A sequel was planned at one point, but Chinchilla had to cancel it due to lack of funds, and instead decided to concentrate on some of their other games. Check out their webpage for more of their products.