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Monochroma, a cinematic puzzle-platformer game, is the first big project out of Nowhere Studios and has been in development for 18 months. As the creative director and designer, it was my job to search for articles that could help us understand the core gameplay mechanics in pre-production. However, I couldn’t find materials that focused solely on puzzle-platformers. This gap gave me the perfect opportunity to investigate core design choices of other puzzle-platformers.

INTRODUCTION

The main part of my research was to define puzzle-platformer elements. Since most of the platformers include some puzzle elements, it is very hard to define which platformers are puzzle-platformer games. So before going into depth with puzzle-platformers, I examined the whole platformer genre with its sub-mechanics. My first target was a long-term game research study of 300+ platformer games that varied from past releases to new games. With the aid of some theoretical reading on platformer topics from The Big List of Game Design, I categorized three main mechanics above all platformer games: Exploration, Action, and Puzzle. All platformer games often contain all of three of these mechanics, but other games tend to focus on one more than the other two. Beyond platformer games, other genres -- including first-person shooters and action/adventure games like Portal, Journey, Papo & Yo, Tomb Raider, and Mirror’s Edge -- have platformer elements.

I will provide examples from a number of platformers to categorize gameplay mechanics and their respective sub-elements. This categorization and their names are symbolic, empirical, and open to many controversies. However, this is a detailed categorization aimed at helping other game designers to better understand the past, present, and future of platformers.

1. EXPLORATION

Exploration is the experience of searching the unknown. Since linearity is a major problem of platformer games, finding the route through reasoning, memorization, and instincts breaks the linearity of the genre. Exploration could be achieved by many factors, but here are the ones I could find.

Locks & Keys

As Metroid did in 1986, most classic approaches to exploration consist of locks and keys. Levels are designed as large mazes. Exploration leads to unlocking, then opening the locked areas. Players must first recognize the locked areas left behind and return back to them after finding the proper access keys. Most of the games that use locks and keys rely on re-spawning minor action elements (e.g., enemies) to make the return trip more challenging. On large-scale levels, proper storytelling becomes more challenging—so cut-scenes often take place right after opening the locked areas. Insanely Twisted Shadow Planet mixes exploration with action and puzzle elements in a very effective way. The game supports exploration by slowly unlocking each weapon as “keys” for “locked” areas. Cave Story, Aquaria, and Shadow Complex are other good examples that use exploration as a major gameplay mechanic.

Procedural Generation

Exploration can also be implemented by procedurally generating levels. Spelunky uses procedurally generated levels to stimulate exploration. The result is a fresh, new challenge every time a player starts a new game. However, procedural generation can be hard to balance—and the rule sets are more experimental.

Experimentation

Experimentation occurs when the player tests unexplained mechanics through self-reasoning. For example, some input control functions don’t need to be explained and could be much more interesting without instructions. For example, in Super Mario Bros., going down the pipe by crouching could be only discovered through experimentation, and the game rewards players who do this early on.

If a platformer doesn’t warn players about what will happen when falling from a high cliff, even death might be an acceptable outcome (at least the first time) because players explored “action-reaction” by themselves. Watching what happens after each action (e.g., pushing a lever, going where the narration tells you not to go) is often very satisfying. Punishing or rewarding players is feedback . . . and feedback is always welcome in games.

Beware: Games must provide enough clues. Players know they might die after a big fall, but they wouldn’t know about it if it happens by a lever push and there isn’t a clue of some sort. Experimenting is only fun when players have options beyond trial-and-error.

Trial-and-error must especially be avoided when designing puzzles. A big risk is inadvertently killing the sense of achievement—and turning players against the game’s rule set. Trial and error should only be used in small doses to take players out of their comfort zone or to make a joke. If trial-and-error is unavoidable, try to place it late in the game. Designers must ensure that players really understand the game’s rules before being confused by trial-and-error traps.

Fake Walls & Invisible Portals

In contrast to experimentation, fake walls and invisible portals can lead to secret paths and hidden rooms. In Jazz Jack Rabbit 1 & 2, some fake walls can be blasted by weapons or action moves. In Sonic The Hedgehog for the Sega Master System, a fake wall containing the path to a secret room can be found by running left and jumping toward the wall. In Gish, there are hidden tunnels obscured by wall tiles.

Easter Eggs & Secret Areas

As a minor exploration element, most games use secret areas to deliver Easter eggs, jokes, bonus items, secret power-ups or alternate endings. In Commander Keen: Goodbye Galaxy, waiting for a few seconds under a specific moon symbol results in a surprising joke. In Duke Nukem, secret areas have massive score bonuses—and in Braid, collectible stars give players access to an alternate ending. Cave Story includes a hell level that is used to challenge other players. Secret areas and Easter eggs add depth and replay value to games.

Alternate Paths

Other exploration elements are alternate paths and secret shortcuts. These may be used to add details about the story or create more replay value. The secret blind path on Limbo is a good example of this exploration factor. In Bug Too!, players may only take alternate paths with specific characters. In Super Mario Bros., there is a warp zone that can be found by walking above the actual level. The secret tunnel in the first chapter of Journey is a good example of alternate paths.

2. ACTION

Action is the most overused element of many platformers and other genres. Action is mainly defined by a lot of focus on movement. Action mechanics could be also described as “physical responses to stressful situations.” I divide action mechanics into two distinct categories: timing and aiming.

Timing

Most of the action-platformers such as Contra use harmful projectiles as major timing element. Enemies may shoot projectiles such as bullets, rockets, laser rays, grenades, fireballs, shurikens and arrows. These projectiles could then be evaded, dodged, blocked, or destroyed. Some projectiles behave as guided missiles and can only be blocked by walls or other enemies. Some projectiles could be time delayed so that running away from them for a time would be enough to evade them. Endless runner platformer games such as Bit.Trip.Runner and Canabalt restrict players from stopping. This restriction changes a formal jumping action to a timing element.

In Gish, a double jump makes the character jump higher (but this requires good timing skills). The game also includes time challenges similar to the final levels in Braid and Trine. For example, the giant fire that follows the player generates adrenaline and requires quick reflexes. Running away from a collapsing building, or a chasing helicopter with a machine gun (Deadlight) are also good examples of time challenges. A simpler but similar approach was used in Super Mario Bros: a time limit for finishing the level. Timing does not depend only on accuracy or reflexes, but also on practical and tactical intelligence.

Aiming

Most aiming mechanics depend on enemy types. Each game contains specific strategies to deal with enemies—which can be eliminated by being jumped over (Super Mario Bros.), killed (or stopped) by melee or guns (Aladdin, Deadlight), compelled to kill each other (Abe’s Odyssey), or evaded (Heart of Darkness). When evading, seeking for non-hostile spaces is essential. A specific artificial intelligence (AI) element is needed to set each enemy’s behavior to different conditions (e.g., when the enemy can see the player, when an enemy is reaching to an edge). Each behavior should be used to describe their strong/weak spots. Platformers such as Super Create Box, Shoot Many Robots, Abuse, and Metal Slug use massive enemy hordes as targets. The player doesn’t have to aim with precision; firing as fast as possible is the only viable option (i.e., “button mashing”). The last third of many platformers turns into a button mashing mess when shooting is a key gameplay mechanic.

Traps are used on platformers to make aiming more challenging. For example, water gaps can lead to drowning on Tomboy (Atari 2600), deadly spikes are fatal in Prince of Persia and VVVVVV, and salt pools and meat saws can do a lot of damage in Meat Boy. There are way too many examples to list here. Some games (Limbo, Deadlight) use high edges and cliffs as pit traps. In Super Mario Bros. and Darkwing Duck, the bottom edge of the screen also works as a pit trap. Most platformers implement jumping over traps by allowing the player to jump from the edge and then land on a “safe” location after a controlled fall. Such traps require careful aiming; others (such as growing and shrinking ponds in Tomboy) add a timing layer as well.

Some platformers attempt to mix both aiming and timing. In Trine, the thief can shoot a rope to specific spots on the ceiling and swing the rope to jump on a particular surface. In Earthworm Jim, a similar mechanic is in place. Double jumping is also very popular among platformers; aiming and timing have never been easier to implement. The wall slide jumps in Meat Boy represent a flawless combination of these two mechanics, and the whole game is centered on them. Other games allow players to jump farther if moving forward (sprinting). Such traps demand both aiming and timing skills from the player. Games such as Prince of Persia and Deadlight include a number of sprint-and-jump traps. It’s also possible to sprint-and-run in Super Mario Bros.—but the game can be completed without a sprint button (with one exception in Level 8-1). Super Mario Bros. also allows players to fire projectiles—but it lacks the ability to aim, so good timing is required to hit targets. Shooting the Piranha Plant over each pipe requires a carefully timed jump—another perfect mixture of aiming and timing. In Heart of Darkness, shadow creatures can dodge electric attacks by crouching or jumping—so players need to take their time before shooting each enemy.

Cooperative Play

For action platformers, cooperative play boosts the fun factor by relying on the coordinated efforts of all players. Legendary titles Snow Bros. (arcade), Sonic The Hedgehog 2, and Super Mario Bros. (console) offer cooperative play. Newer games such as Little Big Planet, Lovers in a Dangerous Spacetime, Shoot Many Robots, Rocketbirds: Revolution! still rely on cooperative play; this adds a new layer of timing and aiming to the game (players must care for each other), which in turn results in deeper, more engaging gameplay.

3. PUZZLE

Puzzles are the essence of Monochroma, so I dug much deeper into the following section. As you will soon see, pattern recognition and physics are vital for all puzzle platformer games. The other elements are useful for having a unique look.

Pattern Recognition

A puzzle may be comprised of many elements, but the most important pattern recognition—the ability to understand the steps one must take to solve the puzzle. If a puzzle doesn’t provide any clues about its pattern and can only be solved by trying all possible conditions, it becomes a trial-and-error experience—which is frustrating to players. Balancing pattern recognition can also affect puzzle complexity. If there are too many possibilities, it becomes much harder to figure out the solution pattern. With too few possibilities, you end up again at trial-and-error.

Vessel is a good example of challenging players with puzzles revolving around pattern recognition. Other games such as Lost Vikings, Fury of the Furries, FLY’N, Trine, and Thomas Was Alone increase complexity by using characters that are able to switch between different abilities. In Gish, the main character’s ability to morph between solid, fluid and liquid states works as a pattern recognition element. A Boy and His Blob uses a transforming blob companion that works in the same way. Boss fights in action platformers such as Cave Story, Super Mario Bros., Darkwing Duck, and The Lion King mix pattern recognition and action elements to add a “puzzle flavor” to each individual battle.

Pattern recognition is a major element in all puzzle games; puzzle-platformers just mimic the same sort of gameplay for their own purposes. The most popular (and simplistic) use of pattern recognition is “n-Levers and n-Doors” or “n-Valves and n-Pipes.” In this specific type of puzzle, the goal is to open all doors or pipes. Each lever or valve has different effect on two or more doors or pipes. If game doesn’t explain the relation between levers and doors, experimentation is required when players use a lever for the first time. Unmechanical uses this puzzle type with buttons and bulbs.

Another popular example is in Tower of Hanoi—which consists of three rods and a number of discs of different sizes, which can slide onto any rod. The puzzle begins with the discs in a neat stack in ascending order of size on one rod (the smallest at the top), thus making a conical shape. The objective of the puzzle is to move the entire stack to another rod, obeying the following rules: Only one disc may be moved at a time. Each move consists of taking the upper disc from one of the rods and sliding it onto another rod, on top of the other discs that may already be present on that rod. No disc may be placed on top of a smaller disk. With three discs, the puzzle can be solved in seven moves. In Monochroma, I re-designed Tower of Hanoi to work in a platformer game. On the re-designed puzzle, there are three boxes with different heights and an elevator that can carry only one box; the player must re-order the boxes to create a pillar to climb up to the exit. A number of ancient pattern recognition puzzles such as Tower of Hanoi have been re-designed and re-purposed for video games.

Physics

As hardware capabilities have increased, puzzle games have relied more on physics-based thinking. This trend includes boxes and wagons to push and pull, chains and ropes to swing, seesaws, hovering platforms, elevators, and much more. These interactive objects play a role in puzzle design due to size, length, speed, friction, weight, shape, density, buoyancy, bounciness, and other physical properties. Trine and Limbo are full of great examples of physical puzzles. In Unmechanical, players may drop stones inside a pool to raise the water and close a circuit using water. In Max & the Magic Marker, players can create interactive objects by doodling different shapes.

Fully interactive objects can be combined with other sub-mechanics to create unique gameplay. Rolling rocks in Rick Dangerous are good examples of combining physics objects with a trap. Also movable bear traps in Limbo are unique interactive objects that differentiate the game from its ancestors. Cloud and monster cannons in Braid are a combination of Super Mario Bros.-themed bullet cannons and cloud platforms which behave as viable physics objects.

Player characters can sometimes be used as interactive elements as well. In Gish and LocoRoco, the main characters are blobs with elastic properties and are integral to the way the physics-driven puzzles work in both games.

Inputs

Restricting and changing the way inputs work can be used to add some variety to basic pattern recognition. In Limbo, hosting a parasite stops the player from turning back. Another brilliant example is in All That Matters: Players control mother and father characters by swapping between them, but both characters’ movements are synchronized. For example, when the father goes left, the mother goes right. In Monochroma, we restrict the player character in certain locations. After the tutorial, players always carry a small child—so running and long jumps are out of the question. Players can only drop their sibling in “safe” locations—and they must not leave their sibling behind. Player input is often used to complicate the timing and aiming gameplay, and it leads players to believe that reality itself is changing along with the game.

Light&Shadow

On many platformer games, the brightness of the environment defines many of the puzzle and action elements. Dark places are used for hiding from enemies in Abe’s Odyssey, Mark of the Ninja, and Black Throne—whereas bright locations are used to destroy shadow creatures in Heart of Darkness. Closure may be the most remarkable example of using light and shadow as a core gameplay mechanic. The game defines that when there’s no light, there’s no wall. An upcoming game, Contrast, also uses the shadows of three-dimensional objects as “run-and-jump” elements. In Monochroma, players carry a younger sibling who’s afraid of the dark and can only be left in well-lit locations.

Environmental Effects

Environmental effects such as wind, rain, and snow are great ways to experiment with puzzles. In Monochroma, players must solve a puzzle by extinguishing a burning barrel by pushing it outdoors, where it’s raining. The game also makes use of thunder in the final puzzle. If the rain begins falling at the start of the puzzle, players will immediately recognize it as another interactive puzzle element. Using environmental elements must be planned in advance and implemented early enough for best results. Even with very long intervals between the two times rain occurs, players easily remember that it is used as a puzzle element. In Monochroma, rain is a major component—constant from start to end. The rain is thus seen initially as part of the game’s atmosphere and not a puzzle element.

Playing with the environment is like firing an emergency flare. You do so once or twice. However, if overused, it can ruin the atmosphere by turning it into a puzzle element because it demands too much attention from the players. Still, it’s a fantastic gameplay element. Players pay a lot more attention to the background after solving a puzzle that uses environmental effects.

Rhythm

Since rhythm is a repeated pattern of sound, it is a great tool for converting pattern recognition elements into timing elements—and thus increasing gameplay depth. Games such as Beat Sneak Bandit and 140 achieve this by offering players a “musical platformer” experience. Rayman Legends includes levels designed as a rhythm game.

Dimensions

Changing dimensions can dramatically modify the environment and the puzzles themselves. One of the best examples is in Fez, where players have an orthogonal view of the levels in the form of 2D platforms and players can rotate the world by 90 degrees while the main character stays put. It’s like a plane is shifting. Giana Sisters: Twisted Dreams uses a similar mechanic, shifting characters and environments at the same time. Sideway: New York is an action platformer that uses graffiti paintings as enemies—and walls, doors, and windows as 2D platforms. The game also creates traps by projecting images over a building, with wall rotations that provide a cool twist on the basic gameplay. Crush allows players to switch between isometric and side-scrolling views to minimize depth; most of its puzzles derive from this “dimensional shift” concept. Other great examples include Miegakure and Oliver & Spike.

Gravity

Reducing gravity can increase jump rates, lighten heavy boxes, and slow down projectiles. Increasing gravity may prevent jumping—and pin interactive boxes to the ground. In Rochard reversing gravity can transform levels with different floor and ceiling behaviors that behave as a dimensional shift. This does wonders for staid pattern recognition gameplay. Changing gravity can also modify the physical properties of interactive objects and characters. Pid uses “gravity changer” beams to solve pattern recognition puzzles and either face enemies or run from them. Limbo, VVVVVV and Thomas Was Alone used this approach well. The Bridge switches from up-and-down to 360 degrees to create interesting gravity-driven puzzles. LocoRoco plays with gravity on a limited basis, only affecting the player character.

Magnetic Fields

Similar to gravity, magnetic fields affects objects made out of iron or steel. In Limbo and Teslagrad, some objects may be levitated and be used as hover platforms, elevators, or obstacles with the help of magnetic fields. This is a way to mix up pattern recognition by only affecting certain objects–leaving the rest of the environment untouched.

Tweaking Time

Braid’s claim to fame is allowing players to tweak time by rewinding inputs and the player character’s position. In some levels, certain levers, keys, platforms, or enemies may be “time revertible”--or not. The contrast makes pattern recognition come alive. The Misadventures of P.B. Winterbottom allows players to create copies of themselves by manipulating time. These copies can interact with interactive elements.

Setting

Changing the setting is not about altering the positions of interactive elements but changing the geography of each level. In Continuity, players may alter levels by swapping entire portions of them. Lucidity is another great example; players can only progress by adding new platforms and destroying old ones. In the platformer Gateways, players can open gates that split the levels with portals.

Other Genres

Platformer developers should take a closer look at games in other genres to come up with unique results. For example, Castlevania II: Simon's Quest and Castlevania: Symphony of the Night includes RPG elements. Guacamelee and Shank pay homage to beat ’em ups. Soccer Kid uses some minor sports elements. The Cave is a perfect mixture of platformer and adventure game. Awesomenauts is also the first MOBA platformer.

Cooperative Play

Cooperative play still appears to be rare in platformers. Both Portal and Portal 2 have strong puzzle platformer elements despite being using first-person perspective. Portal 2 takes cooperative play to the next level by offering brilliant action puzzles that require two players. In one example, two players reach a platform only by jumping on it at the same time from different places—then hitting each other in mid-air.

Timing & Aiming

Some puzzle-platformers use timing and aiming actions as puzzle elements. In Limbo, a winged creature can be caught only if the player takes small, careful steps and waits. There’s also a bunny-like creature that must be lured to the opposite side of the screen. In Limbo and Unmechanical, puzzles combine aiming with gravity when the player must move a box or ball to a particular location. This games make the best of pure aiming as a basic pattern recognition element.

PUZZLE PLATFORMER DESIGN CHALLENGES

Beyond platformer sub-mechanics, I also noticed a few additional puzzle-platformer challenges during my research:

Pacing

One of the most challenging puzzle-platformer elements is pacing. Less action could result in loss of player focus. Narrow pacing should also be avoided; all puzzles must be clearly divided, and players must understand the distinction between each puzzle. This way, players quickly familiarize themselves with the puzzle progression and get rewarded with atmosphere and story. Cut-scenes (Super Meat Boy) or puzzle-free worlds with narrative text pieces (Braid) could also work as pacing elements. Games that don’t place puzzles in separate loading zones might use puzzle-free zones, which reward players with atmosphere and narration without taking away player control.

If players wonder whether they have left something behind or missed an important puzzle, it could mean that there’s a problem with the pacing. One way to deal with doubt is to prevent players from going back. This can be achieved by locking previous stages with doors—but in more realistic puzzle-platformers, it can be handled with cliffs and slide zones. If players fall from an area that can’t be climbed to, the only option is moving forward.

Prevent Stuck Points

The second biggest challenge in puzzle-platformers is preventing stuck points. The only way to deal with this is to effectively communicate with players through gameplay. If the core game mechanics are solid, then players could quickly and easily understand what is going on will be less likely to lose focus.

In puzzle designs, interactive elements such as boxes and elevators may create non-linear possibilities and challenge the player’s creativity. If these interactive elements have non-revertible possibilities that prevent players from proceeding (and fail to kill them), then the players are now stuck. We all know from experience what getting stuck means: frustration, confusion, and a manual re-load of the level to access a recent checkpoint. Worse yet, most consider such a progression break a very serious bug. There a few solutions available, though. Some games opt for a reset level button; others implement a suicide button. Puzzle-platformers that intend to remain on a player’s good side must be designed with this in mind. The game must communicate to the player: “If you are still alive, a solution exists.” Don’t underestimate progression breaks or even single interface bugs; they can completely undermine the player’s enjoyment of the game.

Make sure to tailor each puzzle to prevent options leading to stuck points. Investigating all possible player actions at the design process is crucial. Areas where players may get stuck must be fixed during pre-production. Fixing a puzzle during beta may take weeks—or even a month! So try to plan bullet-proof puzzles before adding them to the game.

CONCLUSION

Let’s end with note I took for myself:

Platformer games are about our childhood. Think about it for a moment. What we do in a platformer is what we used to do when we were children playing at the playground. We’re adults now and don’t need to push a box and jump over it. We never climb wooden ladders or swing on a rope. In Monochroma, I try to celebrate everyone’s childhood by setting the tutorial at a playground. It was my way of saying “thanks” to all the developers that carry childhood memories within and keep the genre alive. Thank you!