Repton

Repton is a classic Puzzle Game written by Tim Tyler in 1985 for the BBC Micro. The eponymous protagonist finds himself, for no discernible reason, in a maze filled with diamonds, all of which must be collected to complete each level. Obstacles to doing this include falling rocks, reptilian monsters and the ever-present time limit.

The game spawned three official sequels and a host of expansion packs, with the last sequel being titled Repton Infinity because it included an editor allowing you to reprogram the way objects behaved, essentially allowing the creation of entirely new games. All the sequels added to the basic Repton format new objects and obstacles, the most important being "spirits" that follow the walls and have to be guided into a cage (and often into a particular cage, working out which being one of the level's puzzles).

The games have recently been re-released for the PC by Superior Interactive, together with the Expansion Pack Repton Spectacular and a forthcoming further expansion, Repton Extravaganza. Although the expansions include further levels for all three games (not including Infinity), Repton 3 is by far the most popular, as it strikes just the right balance in terms of bite-sized puzzles and variety of obstacles, and also allows the character sprites to be redesigned. Many of the expansion packs take advantage of this by placing Repton in a completely different setting, ranging from the American West to the far future.

Tropes include:
 * Aerith and Bob: Repton and his girlfriend Becky.
 * Anti-Hero: Repton is stealing diamonds in the first game, robbing safes at gunpoint in the third.
 * Big Eater: Several scenarios replace the diamond with something edible, for instance plates of food in the "Orient" scenario or pineapples in "Africa".
 * Block Puzzle: Many levels require shunting rocks to link a cage to the wall so a spirit will enter it.
 * Breather Level: "The kraken" in the first game. Also, the hardest-to-reach level in Repton 2 contains a large area of nothing but diamonds.
 * Critical Annoyance: Repton 3 flashes the screen to warn you when the timer falls below 15 seconds.
 * Crossover: Unofficial Repton 3 scenarios exist based on media ranging from Thundercats and Coronation Street to Sailor Moon. Repton the character also appears in another Superior game, Trakka.
 * Difficulty Spike: "Giant clam" in the first game; the second level of "Finale" in Repton 3.
 * Endless Game: The original BBC Micro versions of Repton and Repton 2 looped after completion, although you did get a congratulatory message. Averted in the PC remakes (and in all other games of the series).
 * Exactly What It Says on the Tin: The first screen is called "Screen one".
 * Fake Difficulty: The "Oceans" scenario represents diamonds as pearls in shells, and skulls (deadly on collision) as empty shells, so they require care to tell apart. Safes are hidden pearls, making them invisible until a key (torch) is collected. And then there's the "Future" scenario, in which blank space looks like earth (representing space dust) and skulls look like blank space (representing the deadly vacuum of space).
 * Fungus Humongous: Repton 3.
 * Guide Dang It: The "Repton shuffle", stepping aside from under a rock and immediately pressing the opposite horizontal direction so you push it in mid-fall. There's no hint of this being possible before you reach the first puzzle requiring it. (Still, it's possible to reach the solution on a "when you have eliminated the impossible" basis.) The Superior Interactive re-releases have slightly different gameplay; in particular, on the remakes of Repton 1 and 2 (but not 3) you aren't killed by an egg landing on you, a fact it's important to know for some puzzles (which can be disconcerting for those familiar with the original versions).
 * Hammerspace: Repton can pick up and carry around up to 624 diamonds.
 * Hundred-Percent Completion: The first game awards a point for each earth square you dig, so to get the maximum score you must dig as much as possible. The second game requires digging all the earth.
 * Invisible Block: Three scenarios make the safes invisible; fortunately, this only lasts until you collect a key.
 * Kill'Em All: The family dog, Repton's teacher, a rival motorbike gang, his boss and even his wife.
 * Let's Play: One by testpilotmonkey, a.k.a. Uintathere, and a Pacifist Run by SentinelProxima.
 * Level Editor: Present on Repton 3 and The Lost Realms. Repton Infinity takes it a step further by including a miniature programming language, allowing you to edit the behavior of objects.
 * Luck-Based Mission: The meteors on Repton 2, and some of the fungus levels on Repton 3.
 * Marathon Level: The last level of "Work" is the longest level of Repton 3. Connecting one cage requires shunting a large number of rocks, with spirits going round the level the whole time that have to be dodged and waited for. When SentinelProxima completed this in under 4:00, commenters said that it typically takes them twice or three times as long.
 * But that pales in comparison with the longest level of Repton Infinity, RobboB Level 1. This level is a maze of grass that has to be gradually mowed away, with objects stuck in the grass that have to be carefully freed and transported. Even SentinelProxima took twenty-three minutes to complete this one.
 * Match Three Puzzle: The magiblocks on Repton 4 (one of the Repton Infinity subgames)
 * Meaningful Name: "Repton" sounds like the word "reptile".
 * Must Have Caffeine: Repton himself, in the "Work" scenario.
 * Nintendo Hard: Repton 2. Must be completed in one sitting, and features some fiendishly difficult puzzles and, oh yes, those goddamned meteors.
 * No Damage Run: A requirement for entering the online high scores for Repton 3.
 * One-Hit-Point Wonder
 * Pacifist Run: Possible on the first game. Later games require you to Kill'Em All.
 * Reptiles Are Abhorrent: Both played straight and inverted, since the hero is a reptile, but so are the monsters he fights against.
 * Selective Gravity: Inverted. Rocks and eggs fall, but Repton has complete freedom of movement.
 * Sequel Difficulty Spike: Repton 2.
 * Shout-Out: The "Future" scenario features Daleks.
 * Speed Run: The PC re-releases of Repton 2 and Repton 3 have an on-line high score list for the best speedrunners.
 * Stopped Numbering Sequels: The fourth game is Around the World. There are two different Repton 4s (plus The Lost Realms, which had Repton 4 as a working title), and numbers have now been abandoned entirely.
 * Tele Frag: Avoiding this (by clearing the destination squares of transporters) is a common puzzle element in Repton 3.
 * Theme Naming: The levels of the first game are all named after reptiles and molluscs.
 * There Is Another: Collecting a key opens all the safes on a level, so a second key has no effect, and so there will usually only be one. However, sometimes (e.g. the fourth level of "Encore") there will be an unobtainable key early on as a Red Herring, and There Is Another later in the level.
 * Treasure Is Bigger in Fiction
 * Trial and Error Gameplay: A mild case. Knowing where each transporter goes is often essential to the puzzles (and can only be discovered by trying them), but there are at most four per level.
 * Unexpected Gameplay Change: The occasional "chase" level, such as the last level of the "Prehistoric" scenario.
 * Unwanted Harem: The "OAP" (Old-Age Pensioner) scenario.
 * Unwinnable: Repton 2 if some of the sub-levels are tackled in the wrong order, or if you overlook a diamond before transporting out of a level, since each can only be accessed once. This being a Puzzle Game and all, all the games can be rendered Unwinnable if you fail to solve the puzzles, but on the other games at least you need only restart from the beginning of the level.
 * Unwinnable By Mistake: The first release of Repton 2 required collection of one more diamond than actually existed.
 * Video Game Cruelty Potential: Ever been tempted to drop a filing cabinet on your boss?
 * Video Game Long Runners: Twenty-five years and counting, making it probably the only BBC Micro series that's still adding entries (eight so far, plus the PC-only Spectacular).
 * Violation of Common Sense: In Repton 2 you can run through an egg while it is hatching. Needless to say, one puzzle requires this.
 * Repton 2 also awards points for colliding with a skull (which kills you). The maximum score therefore requires completing a No Damage Run so that you have two spare lives you can deliberately lose.
 * A Winner Is You: Completing the first game simply brings up the message "Repton has been finished!" Repton 2 says "Congratulations! You have completed Repton 2. Now try again." Both games then put you right back at the beginning with your accumulated score.
 * A Worldwide Punomenon: Some of the level titles in the Superior Interactive re-release.
 * One level has the objects arranged so that the map looks like a picture of a medal. Its title?