Analysis: McMillen On Risk & Reward In Video Games

[In this delightfully-illustrated analysis, Super Meat Boy co-creator Edmund McMillen discusses ways to implement retro risk-reward mechanics, now that "lives" no longer matter.] Last time, we talked about "Difficulty", something I might reference in this article, so you might as well check that one out if you haven't. But this week's topic is risk/reward! So what is risk/reward? Risk/reward is a system established by the arcade generation that rewards the player for taking a risk that goes beyond what they are asked to do normally. Pac-Man uses r/r perfectly in many aspects of its design; not many think about it, but this is actually why the game is good. So the first and most obvious aspect of r/r in Pac-Man is the blue ghost multiplier. When the player eats a power pellet, the four ghosts chasing you become edible for a small amount of time and attempt to avoid you. Eating said ghosts will result in score points, and with each ghost eaten after the first, that score is multiplied. The risk here of course is the fact that the ghosts will turn back to normal very quickly, so eating them becomes a race against the clock, if you're too close to one when they become normal you usually die. So the risk here is a loss of a life, and the reward is a higher score -- but the substantial aspect of the reward is the fact that Pac-Man rewards the player with extra lives every 10,000 points, and this is what makes the r/r in Pac-Man important. The player isn't ever required to eat a single ghost; it's simply an optional risk the player can take to rack up score and gain extra lives in the process. R/R In Super Mario Bros. Super Mario Bros. was the first console title to reinvent r/r in ways that had less to do with score, which had basically become irrelevant once games left the arcade. The introduction of coins as things to collect to get an extra life is an r/r mechanic introduced by Mario that was blindly copied by just about every platformer thereafter. The basic idea behind coins in Mario was to use them as r/r that usually put the player in a dangerous situation, and if the player collected 100 coins they got an extra life. Mario also used coins as a way to instruct the player on how to play giving them reference points on where to jump and also hints on where to explore, but I'll talk more about instruction through level design in another article. The second example of r/r in Mario was the 1up mushroom. Hidden within almost every level in Mario was a single block that, when hit, released a 1up mushroom. The introduction of the 1up mushroom was a great way to get the player to take their time and explore the levels a bit more. Exploring each level for that hidden 1up added more danger, and also ate up the player's time limit. 1up mushrooms were also usually rigged to run from the player and/or into kill zones, requiring the player to take an even bigger risk to acquire them. But as most staple mechanics in games, coins and 1up mushroom became easier to get and more abundant as the years went by, and the reward for going the extra mile to get them became pointless when the player no longer needed to worry about lives. Infinite Lives? So how could r/r be applied to a game that had infinite lives? Every chapter in Super Meat Boy has 20 bandages to be collected: seven in the main world, six in the dark world, and six in that chapter's warp zones. The r/r formula with bandages is very similar to coins in Mario, with a few minor changes. So every level in SMB that has a bandage requires the player to collect said bandage, then complete the level without being killed in the process. Bandages are placed in areas that would require more action from the player and put them in much more danger -- most importantly, the player isn't ever required to collect a single bandage to complete the main game. What about the exploration aspect of 1up mushrooms? How can that be applied to a game like SMB? So warp zones act as 1up mushrooms, in the sense that the player needs to explore levels to find them and they are usually put in hidden or hard to reach areas of the game. When a warp zone is found it is permanently unlocked in the level menu. Now bear with me, because this might get a little wordy. Every chapter of SMB has 4 hidden warp zones: 3 in the main game and 1 in the dark world. There are 2 types of warp zones: retro warps and character warps. Retro warp zone: 3 levels, 3 lives per level and 2 bandages to be collected. A retro warp zone is a series of 3 small (usually single screen) levels with a retro visual theme. The player must beat all 3 levels in succession with a limit of 3 lives per level to complete it. Each level set will have 2 bandages to collect, but the player only keeps those bandages IF they complete the warp zone. This was not only a perfect way to bring back old school r/r, but also a way juxtapose the new established rules of difficulty (see previous article) with the retro formulas of the past. Character warp zone: Infinite lives, play as new character, beat the warp and unlock that character. Each character warp in SMB starts with a cut scene introducing a new playable character from the indie community. The warp zone is again a series of three levels that must be completed to unlock that character to be used in the main game -- but this time, there's no life limit, and the player will only be using that character to complete the levels. Every unlockable character in SMB plays differently, usually having a unique ability like double jump, floating or flight. The levels in the warp are designed in a way that forces the player to use that character's ability in order to finish them, in turn teaching the player what advantages that character could have over certain levels previously played by Meat Boy. When the warp is completed, the character is unlocked and can now be used in most main game levels (excluding warp zones, boss fights and other special circumstances) And that brings us to reward: now that lives don't matter, how can we reward the player in a substantial way that adds more to the experience in the same way lives would in the past? Reward = Content unlockables = playable characters / new levels Every 10 bandages collected unlocks something that changes/adds to the current game. and as mentioned above 1 of every 4 warp zones completed also unlocks a playable character. Substantial reward is very important to help motivate the player to push themselves to get better and try more difficult challenges. The difference between unlocking a new way to play the whole game and unlocking a digital badge or hat for your character is quite large, but adding something as in-depth as a new playable character also comes with its own set of difficulties. [This analysis was originally posted on SuperMeatBoy.com, which has more information on Edmund's upcoming IGF-nominated XBLA, WiiWare and PC action platform title.]