The Player's Progress: Designing Levels for Mobile Puzzle Games

Disclaimer: The views expressed in this blog are solely my own 

A Puzzling Challenge

How do you keep players engaged through 1000+ levels of content without continually introducing new mechanics?  This task is no small feat, yet it is the objective of many game designers working in evergreen games as service titles, such as the puzzle game genre on mobile.

I've been working on mobile puzzle games for the past seven months (at a mobile game company called Storm8), and it’s been an interesting experience learning about the way game design concepts are employed in this field.  In this post I want to focus specifically on game design in relation to content creation, the levels that ultimately make up the bulk of the player’s experience.  

As a game designer working on mobile puzzle games,  it is likely at some point you will be doing content creation in support of a live game.  In live support, eventually resources will become scarce for implementing new mechanics, but it will be necessary to continue to use the provided tools to create interesting and previously unseen combinations to keep players engaged.  Don’t despair! The match3 system is mercifully robust, and it is likely you will have a collection of obstacles at your disposal with some natural interactions that can elicit meaningful puzzles.  In this post I want to focus on a tool of traditional game design, the ‘Interest Curve’, and how it can be an asset for structuring levels to engage players.

The Interest Curve

As game designers, our goal is, generally speaking, to make games that excite and engage the player.  One way of thinking of each level in a game, puzzle games included, is a microcosm of the emotional arc of the full experience.  So, each level should provide the player with a similarly developed arc of interest. Enter the Interest Curve:

The image above (taken from The Art of Game Design by Jesse Schell) shows the conventional interest curve, in which each point represents a moment of strong engagement (i.e fun) for the player.  This is a concept that is probably very familiar to people working in games, so forgive me if I’m reiterating.  However, in the form shown, this is still a very abstract concept.  To make it work for us in practice, we need to map it to more concrete concepts within the games we are working on/discussing, in this case mobile puzzle games.

Feeling of Progress

The peaks on the Interest Curve could take on any number of forms of content depending on what game you are working on.  For example, in a first person shooter, both finding a rare weapon on the map or an enemy encounter could register as equally engaging to players depending on the context.  When considering puzzle games I have found moments of progress to be the most relevant mapping for those peaks.  This is still abstract but we can get more specific.  Anecdotally, a strong motivator and reward for most players is a feeling of progress.  This can manifest itself differently for different players and across different games.  A Startcraft 2 player may feel strongly rewarded when they detect that their skill at a certain opening is increasing, as reflected by a better competitive ranking.  In mobile puzzle games, the two main forms of progress within a level are progress on the board (visual progress, the changing of space) and progress towards goals (collecting required recipes, etc).

Board Progression 

Board progression refers to the difference between the visual state of the board at the start of a level and after a playthrough.  This doesn’t necessarily need to be tied to recipe progression, but I’ve found the effect to be strongest when altering the space through play corresponds to the player approaching successfully completing the stage.  The images above are of a level I made for Storm8's Candy Blast Mania. I consider this level, level 1177, one my most successful designs. You can see a very noticeable difference between the opening game board and the board at the end game.  The player must clear jawbreakers (stationary obstacles that block the flow of pieces) in order to fulfill a recipe, but this also increases the usable space of the board and allows them access to the cannons at the bottom of the board which add a score multiplier.  Outlining the flow of the level, and how you expect the board to change throughout a playthrough is a good starting point for designing a level with a good sense of progress for players.

Goal Progression

In match3, bubble shooters and many other mobile puzzle games the player has a set goal count they are working toward collecting (a target score, 100 specific color pieces, etc).  Generally the player should be collecting these at a good pace so they can be close to victory at the level’s conclusion, whether or not they actually win.  However, it is possible to structure levels in a way to ‘spike’ the collection of certain of certain objectives so the player sees a surge of progress.  One way of doing this is to have the player gradually open the space of the level (such as in the examples above and below) so that towards the end of their playthrough they have more bonus matches from pieces that fall in. These ‘surges’ of progress towards objectives are another way to add or emphasize peaks of interest in engagement arc of your level. Believe it or not, watching the tiles drop in, and hoping enough matches come together to tick down the counter giving you the win can be a pulse pounding experience!

In the above image of level 34 from Rovio’s Nibblers, you can see that the opening board has very constrained space, but as the board opens up towards the end game, the player has a high chance of special tiles forming from tiles falling in (these take the form of hungry, friendly fish in Nibblers).  These special tiles allow the player to quickly collect high numbers of their needed pieces.

Games like King’s Farm Heroes Saga and Candy Blast Mania have a built in bonus mechanic that amplifies the values of certain pieces based on adjacent matches, and Candy Blast Mania even has a specific on board fixture that can increase bonuses specifically for this purpose.

A Piece of the Puzzle

Using an interest curve for structured player progression is an important element of level design for match3 and puzzle games, but it is only one element.  Interaction between mechanics, robust existing mechanics that designers have to work with, and defying player expectations are but a few of the many that can come into play, and I hope to analyze some of these at a later point.  For now, I hope you enjoyed reading and feedback is welcome!