Theoretical Disclaimer

The most valuable thing I learned during my time in Music Theory was that theory comes after the fact.  The entirety of the subject comes from observation of music that has already been written.  This little rule became a bit of a mantra of mine that I would repeat often when doing analysis for class and trying to figure out whether I was looking at secondary functions, borrowed chords, or some elaborate combination of the two when the truth is it could be all of the above depending on how you want to look at it.  

Mine (and other more legitimate discussers of the subject) analyses and theorizing on games is no different than the work of music theorists:  Theory (in this sense at least) is just an attempt to understand what makes something good. However, music and games are much a matter of personal preference, and so the interpretation of the elements of a game can also be a matter of perspective.

Music Theory can be taken with a grain of salt, because the ultimate rule with music is Do What Sounds Good.  If the musical experience is ultimately improved by disregarding a rule of theory (which are really more aptly called guidelines) then it is the right choice.  20th century music threw out all pre existing rules more often than not, and being the last thing in our course curriculum left many of us to wonder what was the point of the rest of the 4 semesters worth of study if at the end all we did was throw it all away.  The truth is that we probably would not even be able to properly describe what was being thrown away without studying all of that other stuff in the first place. 

In this way Theory provides a common language for describing things.  If I wrote I bVI IV VI on the board of a music theory class, people would understand it.  They could probably even go over to the piano and play it in some form.  They could probably even write out full 4 part harmony from it.  Without theory, that would require something restrictively specific like writing out the frequencies each pitch sounds at.  Game Design is generally described in terms that are common to games themselves, as well as borrowing from related fields like Human Computer Interaction.  I feel that there needs to be terminology created that can describe games with the same range of granularity that music theory has. 

The point isn't to codify some set of standard for engineers to follow to make an excellent game, but to look inside and see what all the pieces are and how they fit together, and with that new knowledge be able to more solidly build our own work, and maybe put together those elements in a way that we would not have considered otherwise.

And thus is my disclaimer:  While at times influenced by the work of many insightful theorists, this is ultimately me coming up with terms, and applying them to games as makes sense to me.  Within this little sphere of influence I will treat them as fact.  To everyone else, consider it to be advice that if not good, is at least well thought out. 

Power Sources

Previously, I went through a bit about what a Power Up is.  This time, I will discuss ways in which Power Ups in all their success promoting, gameplay modifying forms are actually seen in the game.  Here are some categories that I have come up with, keeping in mind that some Power Ups can fit  into multiple categories:

Utility

These are the type that do not modify the gameplay directly, but still help the player towards success in the game.  These do things like replenish health and ammo, permanently improving capacity, unlocking new passageways, money, experience, etc.  It isn't that these power ups can't change the gameplay, it's more that the change it has on gameplay per individual item is insignificant and the change in gameplay is psychological on the player's part.  Someone with higher health capacity and ammo is more likely to take more risks and be more liberal with their ammo, but the gameplay itself hasn't changed, just the way the player feels about it.  And even though these items don't effect the gameplay inherently, the mere inclusion of a power up will always effect gameplay (typically lowering the difficulty as well).  Things like coins in Mario have long been used to draw players towards the correct path, even though their collection does not modify gameplay, and even their individual utility to the player is fairly insignificant.  Healing items in RPGs are another interesting one, because proper management of them can be a fairly integral part of the gameplay.  These types of power ups are nearly ubiquitous in gaming, and it is generally harder to create a game without implementing these in some way.  The regenerating health that has become a staple in modern FPS games is actually a really good example of this.  Whether a design like this is an improvement over health lying scattered around is something that varies greatly.  The value of these Power Ups is mostly dependent on their rarity.  Extra lives can be a great reward to skilled risk takers in a game, but if they are common enough that the player easily hits the maximum, there might as well not be lives at all. 

Temporary

These are Power Ups whose effect is temporary.  Whether a time limit, damage, death, running out of ammo, or being single use, these will run out.  These are the primary type of Power Up found in platformers, and to a lesser extent includes the weapons found in many FPS games and classic shoot em ups (death and a new stage generally resetting the weapons and abilities the player has accumulated).  Essentially anything that does not persist can be seen as part of this category.  These are most commonly seen in linear games (meaning the game is broken down into stages, and the goal is to get from point A to B, however circuitous that path may be) though they do show up elsewhere.  This type actually rewards player skill, since these power ups can be easy to find but can only be fully utilized by proper skill from the player (getting extra lives from an invincibility star, maintaining a fire flower the entire game, saving the rocket launcher for a later tank instead of wasting it immediately on infantry).  Their temporal nature is also valuable because they can add variety without changing the baseline experience, but the game has to be designed to be completable without these temporary Power Ups, with only a few exceptions.  A rare example of this is the Hypermode ability in Metroid Prime 3 (you may choose when you enter it, but it's still temporary) turns on for the remainder of the game once the final area has been entered, which causes a permanent shift in gameplay.  This sort of design is definitely more the exception than the rule, both in its forced use at the end of the game, and in its ability to be chosen to be entered at any time.

Granted

These are permanent Power Ups that are given to the player during the course of gameplay.  Unlike the previous category, these usually come after some sort of accomplishment in the game like finishing a stage, defeating a boss, or finding some obscure and difficult to reach corner of the game world.  Because these are permanent, they effectively change the baseline experience for the game, which might make one wonder why this would be superior to something temporary or having all of the capabilities immediately.  Besides the obvious at this point (variety) there is also the difficulty curve of the game.  Granting abilities after the player has overcome a challenge that proves their proficiency with the current gameplay mechanics allows them to learn incrementally.  This is a much more effective system than a tutorial info dump of everything at the beginning of the game.  At the same time, there are some serious balance complications with this, as granting a large amount of Power Ups over the course of a game can cause many of them to be used once and forgotten about.  Also if granted to close to the end of the game, it ends up having very little actual application, which can mean a great deal of time implementing a Power Up with little benefit to the whole experience.  Portal 1 is an excellent example of its use, as there are only 2 Power Ups:  Creating a portal, and Creating a second one.  You don't get each one until you've managed a number of different situations first that proves your mastery, but the majority of the game is spent utilizing those two Power Ups effectively. 

Chosen

These are also permanent (with few exceptions) but instead of being received at given points in the game are chosen by the player, typically by means of some list on a menu and spending some form of points.  This gives the player gives some options in terms of strategy and play style that is not available otherwise.  However, non-determinism of any sort can be very hard to design around.  Whether intentional or not, there is often an optimal order, and some other combinations could be severely worse.  Designing the game difficulty to follow the least optimal order could leave it completely unchallenging to better set ups, and designing for the most optimal could make it downright impossible to worse set ups.  Which means the best solution is to plan for something in the middle, which may still be a far from either extreme.  The ideal solution would be to balance the possibilities well enough that there is no optimal order (or at least very subtle differences) but that is difficult without greatly removing the actual variety of it.  These sorts of Power Ups are common in the form of research upgrades in Real Time Strategy games.  In this case the player starts from scratch at the beginning of each level, so an optimal order for acquiring them can simply be seen as part of the overall strategy, and a poor decision will only effect the immediate level.  In a hack and slash (another place these have become common), the cumulative choices since the beginning of the game could have consequences much further out.

Slotted

These are Power Ups that are selected from a pool of possibilities, with a finite number being usable at any one time.  This has become popular in many multiplayer games lately due to the larger meta game strategy that it allows.  This of course has many balance issues, as some combinations can be overpowered to the exclusion of all other strategies.  If the number of slots and size of the pool can be increased, balance gets that much harder, and individual Power Ups can't be very significant due to the differing quantity.  This type rarely stands alone, as slots and Power Ups have to be acquired somehow. 

Chained

These are Power Ups that have others as a prerequisite.  This type can not really stand on its own, but is a combination with others (Mushrooms before Flowers, Skill Trees, etc).  This allows for connecting different types of Power Ups into very complex formations. The prerequisite is in the actual possession of the Power Up, not in the gameplay side effects.  This is most often used with Slotted, allowing certain Power Up effects to get progressively more complex, but Chosen is often included as well.  This can keep player choices from completely unbalancing the game. 

Compound

These are Power Ups that are useless individually, taking effect after a group have been collected.  This is another type that does not really stand alone, with Utility being the most common combination.  There is absolutely nothing preventing other combinations though. 

In Practice

Naturally, there isn't a game that uses any of these exclusively, even if you only consider Chained and Compound an extension of these other types.  But this helps shows some of the concerns that different implementations of Power Ups can have.  Some of the issues come from choosing one type where another type would be better, others come from just not considering thoroughly the complexities of a certain implementation.  And of course, the more complex the implementation gets, the more to consider.  Leveling systems are a specific combination of these more basic types of Power Ups, and I'll get into more the issues with those later. 

Powering Up

I (and at least half a million other people in the world) had the opportunity to play the Guild Wars 2 Beta Weekend Event this last weekend.  Having Played Guild Wars 1 since before its first birthday and logging more hours than I really care to admit to, I was looking forward to this quite a bit and thoroughly enjoyed it.  And I think it's important to clarify that first and foremost:  I liked the game, I am looking forward to the next weekend event, and I do not regret preordering the Collector's Edition in all its costly glory.  Giving my wife a spin on it made her start shopping for a new computer so that she could play it with me when it comes out. 

This isn't a review of GW2 or an analysis or anything.  I expressed many of my thoughts and concerns already on their forum, so I won't get too specific about that.  I'll give my detailed thoughts once it's not a beta anymore and I have an opportunity to get to an area that isn't effectively right outside the city gates.  Nonetheless, It has caused me to think rather extensively about the actual value of a game mechanic that features so heavily in it and its ilk:  Leveling. 

I don't think that leveling is bad, really.  I've been a fan of RPGs for a very long time, and it is generally the main commonality between eastern and western RPGs that actually allows them to even be identified together.  It also gives a nice quick look at the relative power of your characters or your enemies without having to get into a whole lot of nitty gritty.  I just think that it is a mechanic that can be vastly misused.  But that's getting ahead of myself.  After all, it's important to understand the purpose of a leveling mechanic, which is to Power Up the respective player avatar(s) in a game. 

The earliest example of a power up that I can think of is the power pellets in Pac-Man.  I think this is also a very good example of a power up, because while it was in effect it actually changed the gameplay mechanics.  There are two very simple goals in Pac-Man, collect all the pellets and avoid the ghosts.  The power pellet actually turns that goal on its head, and all the sudden you're the one chasing the ghosts down.  By either eating them or merely putting distance between yourself and them you are also improving your odds of success, which is possibly the more important effect as a player, if not the only one that they are truly conscious of.  So you could say that a power up is anything in a game, whether it be an on screen item that you collect or something you select from a menu at some point in the game or whatever, that allows a player to progress further in the game and optionally changes the way the game is played in some way.  I posit that the power ups that accomplish the first goal THROUGH the second one are the ones that will be more memorable and fun for the player. 

Another fairly early example would be the original Mario Bros.  In this game, you had the capability of running around and jumping on enemies and platforms, and hitting blocks from below to attack enemies and gain power ups.  The Super Mushroom is probably the most iconic power up in all of gamedom.  Certainly, this item was valued for the extra hit it granted you, but it also changed the gameplay significantly in ways that actually were both good and bad.  Being now 2 tiles tall, you could no longer fit through paths 1 tile high, forcing you to take certain paths.  You could also now destroy many blocks by jumping underneath them (allowing access to new paths), which could actually become a liability if you needed those to traverse the level.  It also allowed you to find the Fire Flower, which did not actually grant you an extra hit, but the ability to attack enemies from long range, which is a far less subtle change to the gameplay style.  This ability improves the player's chance of success far more than the super mushroom, and it did it solely through the change in gameplay mechanics. 

Less linear the design gets, the more important power ups become, as the power ups generally act as the means to which further exploration is enabled (and therefore improving the player's chances of winning).  And these usually vary greatly.  In the Metroid series, they ranged from jumping higher to being able to walk safely through lava, to allowing you to run through obstacles at a high enough speed.  Each one of these changed the gameplay (jumping to new paths, running into lava instead of avoiding it, searching for open stretches of land to run through) as the game continued.  Compare this to something like Doom, where the key cards merely allowed you to go through the matching colored door.  Of course, Doom's weapons are also powerups, and the different way each one behaved changed the gameplay when using that weapon, as well as the overarching weapon choice for a given situation. 

These are important to multiplayer games as well, as they can change player tactics quite a bit.  One player having Invisibility in a First Person Shooter (assuming the other players know about it) will cause opposing players to be less conservative with ammo, while the one with the ability will be less likely to give away their position by firing.  Having a damage multiplier will generally cause the player to fire continuously in the hopes to maximize its effect, while other players will usually run directly away from them.  Something like the Jump Boots from Unreal Tournament will make players choose their location differently to either use it as an evasion or to reach a tactically superior position that is otherwise unaccessible. 

So powerups in general are pretty great.  Players like them because it helps them beat the game, and also because it makes for a more varied and interesting experience.  If you took the power pellets out of Pac-Man, it would probably still be playable, but more difficult and much more repetitive.  But there are many ways to implement them, and some are more well suited to certain things than others.  More on that next time.