The Mash Flow

Mash flow is the very simple concept of what exactly your fingers are doing while you're fighting a group of enemies in a beat 'em up game. There are a handful of integral types, and while there are many subtle strains of these types, I'm going to break down and scrutinize the big boys.

Type 1: Super Traditional

I call this Super Traditional because the very first generation of beat 'em ups (specifically Taito's Renegade and Technos' Double Dragon) took a two button approach. The input scheme was identical; one button was for punch and one button was for kick. Either button would start a very straightforward combo that you could either see to the end, cancel by ceasing input, or get hit out of. It is very important to note there was no interplay between the two basic flows, it just seemed like it because you could start one combo in the middle of the other. What's fascinating to me about the manifestation of beat 'em ups and their early use of this very rigid style of mash flow is that in all fairness, every attack in the combo past the very first attack was just a satisfying formality; you could design the same game without even having combos. But they did it anyway because it was incredibly satisfying to players. So much, in fact, that we've been iterating on this basic formula for 25 years.

Type 2: Traditional

It didn't take very long for game designers to realize they were misusing an entire button with a trivial redundancy so they smashed the game's important mechanics into one button. Thanks to this decision, the second generation of beat 'em ups (Final Fight, Streets of Rage, Golden Axe, all the way up into the later era of Aliens Vs Predator, Battle Circuit, and Armored Warriors) were much more elegant and had the players navigating the game environment, staying clear of attacks, and then pinpointing the right moment in which to execute one very useful string of attacks by mashing one button. Eventually the genre developed a "special attack" button that would execute a unique mechanic that was very powerful but also very limited in use. Before the implementation of this ability on its own button, most beat 'em ups let players perform this by pushing the attack and jump buttons at the same time. This was too difficult for the average player to do reliably, hence the move to its own button.

Type 3: Gap Timed

One of many concepts the first Devil May Cry introduced into the world of beat 'em ups is the idea of branching live combos into completely different combos by waiting at key points in the combo for a split-second before hitting the attack button again. For example, pressing A four times in a row would get you a fundamental standing combo, but pushing A twice, waiting for the second attack animation to approach completion, and then pressing A two more times would get you a completely different combo. The benefit of this method of mashing is that it's varied but elegant. The downside is that most players struggle with the execution of this type of combo and give up on it, which is understandable.

Type 4: Circuit Jumping

Heavily popularized by Team Ninja's Ninja Gaiden and Sony Santa Monica's God of War, beat 'em ups eventually returned to a two-button input scheme that offered "light attack" functionality on one button and "heavy attack" functionality on the other. Admittedly, this can feel a lot like the Super Traditional mash flow but there are two key differences. The first key difference is that the attack types don't just look different, but they feel different and have different effects. For all intents and purposes, attacks on one button in Super Traditional mash flow games are functionally identical to attacks on the other button, they just look different. The other key difference is that modern beat 'em ups have formalized the dynamic use of the two buttons so that it is still considered one combo if the player decides to jump into the other circuit. This was certainly not the case in Super Traditional games, which is another reason the second button was ultimately useless. Circuit Jumping mash flow allows the player to switch mid-stream between the light and fast combo they have started to the slower and more powerful combo they want to finish with, or vice versa. Once they have jumped, however, they must follow through to the end of the new circuit.

Type 5: Super Flexible

This super modern and very newly employed mash flow is an incredibly flexible and intuitive flow that allows the player to switch back and forth between attacks types on two different buttons whenever they want as a dynamic response to whatever is happening around them. As far as I know, the only games that have implemented a mash flow like this are Bayonetta and Dante's Inferno. To be fair, Bayonetta is much more nuanced than this diagram would suggest, but for the most part the idea is on the mark. While it does have the potential to be very exciting and expressive, the danger with this mash flow (as evidenced by both Bayonetta and Dante's Inferno) is that your attacks can lose meaning. I say "danger" and not "problem" because I don't believe this issue is inherent to the flow type, but to the game. In Dante's Inferno, none of the standard attacks on these buttons are particularly meaningful or different from each other. In Bayonetta, the problem is fascinating; there is such a vast amount of meaningful attacks and combos that many of them are rendered meaningless by our human habit of "sticking to what works". I firmly believe this idea can be wrangled in to create something that feels dynamic but doesn't get turned to mush by the player's brain when they are knee-deep in an encounter.

I wrote this post to create new language. If you started using these terms to describe the types of combos you like and want to implement it would inject joy directly into my biological joy parser.

Difficulty In Beat ‘Em Ups

The idea of difficulty in a beat 'em up seems straightforward, but once you dig in and really pick apart why a particular game feels so easy or so hard, you'll quickly find it's pretty hairy. Keep in mind this is not a discussion about difficulty on the higher game-structure level; for a couple notes on that check out the previous post on Challenge Vs. Punishment. This is about the difficulty on the moment-to-moment encounter level. I've found that you can really evaluate it by posing a few really important questions:

1. Who is attacking the player?

This is simply about assessing an encounter at various stages and then planning accordingly. One of the key differences between an easier and a more difficult encounter is how quickly and carefully the player has to undergo this process. Now the first thing the brain is going to do is register the enemies by their appearance. Ideally they are as visually intimidating as they are mechanically threatening so even when the player has never encountered an enemy type they'll have an idea of what they're up against. In a well constructed game, the different enemy types are recognized effortlessly and the player can easily recall exactly what those enemy types are capable of, assuming they've been previously defeated. The very next thing the brain is going to do is go into a bloodlust and what separates a good player from a bad player is whether or not outright mashing begins here. I make the distinction because these factors we're discussing will determine whether or not the average player is going to survive that impulse to mash.

2. When are they attacking the player?

This is about two symbiotic possibilities: the frequency of individual enemy attacks and the coordination of attacks between multiple enemies. The frequency of attacks is pretty straightforward; enemies perform a dice roll at the end of a designer-specified cycle and the quicker the cycle the more intense the pressure on the player is. This cycle can be as short as a single second (sometimes less in the more sadistic sectors of the genre) or as long as a minute, depending on the game, enemy type, and difficulty mode. But the real secret sauce is in the enemy group behavior. Attack coordination (or lack thereof) is easily one of the single biggest contributing factor in determining how difficult a game of this type is. For example; in God Of War the player will rarely be attacked by more than one or two enemies at a time but in Ninja Gaiden, enemies don't give a flying fuck about what other enemies are doing and the player is under a constant barrage of attacks. Obviously this changes how you play the game and cannot be glossed over in the design process. For a much more detailed analysis about the nuances of group behavior, check out this great 2009 write-up by Tom Smith, a then creative manager at THQ who was helping with Nihilistic's Conan at the time.

3. How are they attacking the player?

This is about identifying the attributes of an enemy attack. The player is relying on a set of primitive behaviors and simple cues to determine how dangerous an enemy and their respective attacks are. One of these attributes is the "tell", or the visual cue that indicates to the player that an attack is about to occur. Typically this just means a warm-up animation (for example, an enemy swinging their sword behind them in an exaggerated fashion before attacking) but could also mean a distinct sound or effect. Tells can vary greatly in form and function, but it goes without saying that having no indication that it's time to prepare for an attack is much more difficult than having it broadcast way before it happens. The more mechanical aspects of an enemy attack are much easier to observe. What does it look like? How much damage does it do? What does it feel like getting hit by it? What's really interesting is that these factors can come at the player in all kinds of crazy combinations, like attacks that don't look very powerful but hurt the player very much, or attacks that are spectacular and intimidating but ultimately trivial. In some (too many) games there are generic looking attacks with non-trivial effects and this oftentimes feels unfair. It's a very strange problem but it boils down to minimizing the discrepancies between what the player is looking at and what the player feels.

4. What can the player do about it?

This is the million dollar question once it's all said and done and wraps up the high level difficulty equation. This can make or break the game and all of the enemies in it or alternatively, it can render the player powerless. The answer is found in the flow of combat and deals specifically with what ability the player is given to deal with inevitable enemy attacks. As stated in the previous post about defense mechanics, sometimes it's a block or a dodge and sometimes it's nothing, but whatever it is and however it's implemented are very important factors. Unfortunately, most games don't have a very rewarding answer to this question, and the only tool the player is provided with is the ability to simply continue attacking once they've survived an attack. Not only is this why most beat 'em ups feel difficult, but it's also why they oftentimes feel very tedious! The player must simply repeat the "evaluate, survive, attack" process over and over and over again.

Here are some case studies:

God Of War:

1. Who is attacking the player? Small to medium sized groups (3 to 10) of reasonably threatening enemies that encircle the player character.
2. When are they attacking the player? Carefully coordinated enemy attacks across all types of enemies at regular intervals; no more than one or two enemy attacks at a time.
3. How are they attacking the player? With moderately fast attacks that aren't particularly damaging but are often very extravagant and powerful looking.
4. What can the player do about it? The player can identify the attack tell and dodge out of the way. Once recovered the player simply continues to mash.
5. Concensus? Is not very difficult, but feels very difficult.

Ninja Gaiden:

1. Who is attacking the player? Small groups (3 to 5) of fairly threatening looking enemies that form groups around the player character.
2. When are they attacking the player? Every enemy will attack whenever they want at very frequent intervals.
3. How are they attacking the player? With very fast and damaging attacks with little to no tell.
4. What can the player do about it? The player can maintain their block stance or perform a quick dash out of the block stance, but since enemies attack so quickly there is no incentive to dash. In any case, the player may then continue to simply mash.
5. Concensus? Is very difficult, and feels very difficult.

Bayonetta:

1. Who is attacking the player? Small to medium sized groups (5 to 15) of very threatening looking enemies that encircle the player character.
2. When are they attacking the player? Lower level enemies will attack in turn at regular intervals and higher level enemies will attack whenever they want at regular intervals.
3. How are they attacking the player? Some enemies attack from a distance with very weak projectiles but most enemies have powerful close combat attacks with fast but very noticeable tells.
4. What can the player do about it? Bayonetta is a remarkable exception in this regard; the game rewards the player with a brief window of excessive power against all nearby enemies when they perform a last second dodge against any one attack. Once this is window has closed the player may then continue to regularly mash.
5. Concensus? Is very difficult, but does not feel very difficult.

Dante's Inferno:

1. Who is attacking the player? Small to medium sized groups (3 to 10) of goofy looking enemies that haphazardly encircle the player character.
2. When are they attacking the player? All enemies across all enemy types coordinate their attacks so that only one or two enemies are ever attacking you.
3. How are they attacking me? Most enemies have close combat attacks that have barely noticeable tells, but they are also not very fast or damaging.
4. What can the player do about it? You can maintain a block stance or dodge, but the dodge is so poorly implemented that it is rarely used. You can also parry in the same way God Of War lets you parry but it's not rewarding enough to hone and employ. After any of these things the player may simply continue to mash.
5. Concensus? Not very difficult, and does not feel very difficult.

Every game does things a little differently so it's worth spending some time breaking them open, especially if you like the way one feels and plays when you've got your hands on it. In any case it's a very delicate balancing act and has so much to do with how your game feels. With that being said, keep in mind that it is still a matter of preference! Decide how difficult you want it to "feel" for the player and then build around that.

Characters Adhering To Input

One of the most fascinating thing about beat 'em ups (and by extension, fighting games) is the way they manage and deliver input from the player. It's easy to assume that whatever input the player provides gets pushed directly to the character object, but this is far from the truth. More often that not, the input is being parsed by the engine and chopped into manageable sequences before it gets fed to the character and expressed. For example, the necessary motion to execute Zangief's 360 piledriver in Street Fighter 2 is a 360 rotation of the stick followed by a punch. It would seem that the game is waiting for the stick to make the full rotation but in actuality it is only really listening for about 270 degrees of rotation. You may think you're going through the motions when you execute the move on a full 360 rotation but truthfully, it hit 270 degrees and started listening for your punch input. You just did it fast enough that you wouldn't ever notice.

Now imagine you have a 60 frame opening attack animation for your beat 'em up character's opening attack. You execute the move with a button press and now you want to provide the input for the next attack in the combo. The good news is that the engine is immediately listening for further input from you because it knows this attack starts combos. The bad news is that your mashing fingers might just be so fast that you give the engine the input it needs before you've gotten to the point in the attack animation that the attack actually occurs. If the engine were to cut off the attack as soon as it gets your input then you run the risk of having an attack stop during the cool-looking and effective part of the animation and if you're SUPAH FAST then you run the risk of moving onto the next attack before you've even turned a hit box on, rendering the attack useless. So this is where the modern combat engine gets savvy. It immediately listens for your input when an attack starts, but instead of instantly acting upon your input once it gets it, it waits until a key frame in the animation to move on to the next attack in the sequence. If the animations are properly constructed you won't notice the gap and it will still feel powerful and fluid.

Interestingly, this is a much larger risk now with 3d games then it was with traditional 2d games because traditional games' attacks only lasted a couple frames in the first place and hit boxes were instantly extended. So when you cut off the animation with your mashing you still successfully attacked, although you would not likely perceive the cut off. In 3d, you can't really create decent-looking animations that don't have some anticipation (animation terminology for build-up; think about how Bugs Bunny lifts his knee up across his body and clenches his fists before comically running off the screen). As a case study, Bayonetta has 4 to 6 frames of anticipation on average for her opening attacks and that's before the frames it takes for the actual attack to occur, which is anywhere between 3 to 30 frames. Even at a bare minimum of approximately 10 frames, that's more than enough time for players to provide the input and kill the attack and create all kinds of problems.

If you want to investigate this for yourself, check out the multitude of fighting game ports on home consoles that have training modes that show you your input while you play. It's amazing to watch what goes in and what actually comes out.

Meaningful And Elegant Defense

If attack mechanics are the yin of combat then defense mechanics are the yang; at least whenever you're engaged to things that can attack you back. The coolest thing about defense mechanics is that there are so many ways to handle the "problem" of enemy attacks but the crappiest thing about them is that they're so easy to render meaningless. In more games than I'd like to admit, you're given defensive maneuvers that you simply don't use (for any number of reasons) or you try to but they don't help you. A good defense mechanic looks good and feels good, but must ultimately be functional. Enemies are going to attack no matter what and in the interest of elegance, there should be as few ways as possible to deal with this. Having too many is confusing, having too few is frustrating, and having any at all that are meaningless are buttons wasted. Furthermore, the usefulness of the given defense mechanics are going to directly and heavily influence the difficulty level of the game.

Now let's take a look at a couple choice examples of defense mechanic usage:

Ninja Gaiden - Holding the Left Trigger/L2 button snaps the character into a defensive pose that prevents them from taking damage when struck. To be honest, I picked Ninja Gaiden somewhat arbitrarily; most modern beat 'em ups use this exact defense mechanic. The debilitating truth about blocking is that while it's just not exciting to sit there and hold a button while you get slapped with repeated enemy attacks, it works so it continues to get employed. There are certainly games which have pushed this idea a little bit in an interesting direction, but most of these instances have suffer from poor execution and fail to evolve the mechanic. Now in the defense of the block mechanic, it is surprisingly difficult to break, but this doesn't make it any less disruptive. Sometimes this is intentional, as is the case with Ninja Gaiden. You cannot cancel attacks by blocking, making you very carefully consider when it's time to commit to a full fledged combo attack. The result is a highly tactical combat experience, but in addition to being very difficult, it compromises the highly kinetic combat experience that a lot of us play beat 'em ups for in the first place.

God Of War - Pushing the right analog stick in any direction quickly rolls the player character in the direction of the push. Furthermore, it cancels anything the player might be doing: attacking, moving, blocking, etc. And this applies to any attack in any combo, provided it's on the ground. This is actually one of the many reasons God Of War feels so responsive. You can react to the enemy character's carefully designed visual tells without cutting off your aggressive attack flow. The game also provides the player with a block, but not only is the block primarily designed to facilitate a completely separate mechanic, but both block and parrying (the facilitated mechanic) aren't necessary. You can play through the entire game without ever utilizing either of them. So God Of War almost wins the award for most elegant defense with its amazing rolling mechanic, but drops the ball with the perfectly good input real estate that is wasted on the block/parry. In all fairness, it would have been easy to make the block/parry meaningful by creating an enemy type that enforces it, but at that point you're contriving the simplicity of the combat.

Bayonetta - Pushing the Right Trigger/R2 Button makes the player character quickly dodge into the space just outside of the engagement zone. Like the roll mechanic in God Of War, it can and will cancel anything you're doing and immediately execute. Without directional input she slides directly backwards but otherwise she dodges in whatever direction you choose. It's exciting because it allows you to maintain your aggression in the same way the God Of War dodge does. But where Bayonetta takes it to the next level is that not only can the dodge be done in the air, but it does not interrupt your place in the combat flow! If you continue to provide attack input once the dodge is complete the combo resumes exactly where it left off. It's incredibly graceful but is also dependent on some well designed under-the-hood features; the game knows to slide the character right back into the face of the enemy when the player does this successfully. In any case, the mechanic is brilliant and elegant and super fun and most importantly, it allows the player to continue beating the crap out of enemies until their fingers disintegrate.

Aliens Versus Predator - Traditional beat 'em ups solved the problem of defense by not actually having defense mechanics! You were responsible for positioning your character in such a way that they simply wouldn't get struck. It's ultimately the most straightforward way of protecting yourself, provided there isn't poorly designed enemy AI breaking this completely. But when done correctly, the "don't get hit" mechanic is the cleanest way of keeping the player safe because they've already taught themselves how to move. The next logical step is to develop the skill to move in creative yet cautious ways. Where Aliens Versus Predator shines is in the highly mobile attack mechanics that give the player all they need to get out of a bind or even avoid it completely in fun and attractive ways. Now in all fairness, this style of defense was made realistic by traditional beat 'em ups because they were 2d and that kind of tactical positioning was reasonable. Once the genre migrated to 3d it all changed. Not because it's any more difficult to track enemy positions in 3d games (provided you've got a camera that's doing its job), but because of a cosmetic change that occured in the move to 3d; enemy characters in 2d games could afford to simply attack to the left or right as you shuffled about. In 3d they look utterly ridiculous if they're not attacking directly at you, and having a group of enemy characters all attacking directly at you breaks the careful positioning game of yore.

As always, you should do what you think best serves the combat experience you're cultivating.

Evaluating Beat ‘Em Ups

I often find myself turning on a beat 'em up I've previously played (or one I recently purchased knowing about its beat 'em uppery) in order to evaluate how things are done across the genre. There are a lot of key items I'm looking at and I figured I would publicize them so that they can be utilized and expanded on. Now before I even get into this, it's important to know that most of these items are not absolute in the sense that there is a right or wrong way to handle it, it's ultimately a matter of designer preference.

Character Movement Minutiae:

• Does the character accelerate or decelerate when they run? (You almost never see deceleration in action games because it's really important to not slide right into enemy attacks when you think you've stopped moving, but it's a good thing to keep your eye on.)
• How fast does the character move? (The speed of a character oftentimes has a lot to do with a game's level of tedium and pacing.)
• What is the arc of the character's jump? It is far or short? High or low? (Modern beat 'em ups don't permit long jumping distances because it would make escape from a melee less challenging.)
• Does the character adhere perfectly to your input? (They most likely don't; pay attention to this and let it blow your mind. Beat 'em up characters are doing a handful of subtle things for you that you'd normally never notice.)
• What happens when the character receives 180 input?
• When exactly is the character permitted to jump? To double jump? (Sounds self-explanatory but if you get weird with it you will be surprised.)
• How much control do you have while the character is airborne?
• How are animation transitions between states handled?
• What happens when you cease all input during various states, versus what happens when input is consistent? (Characters tend to do a lot of flashy/meaningless things when there is no input simply to charm the player. But most games know better than to let those things break the game, so they will behave differently when there is input. For example, watch how characters undergo a landing animation when you come out of a jump without input but then watch how they completely skip it if you are telling the character to move as they land.)

Character/World Interaction:

• Does it take long to walk across a level/stage? (Very important tedium/pacing question. Sometimes shortening/lengthening a level can make it less tedious or more meaningful.)
• What is the gravity of the main character's world? How fast or slow do they fall? Does gravity ever change? Do enemies adhere to the same gravity? (You'd be surprised at how inconsistent and varied gravity can get across an individual game.)
• Are enemies out-runnable or not, and why?
• What happens when you push directly against an enemy with your main character? (This is surprisingly consistent, actually, but good to be sure of.)
• What happens when you jump directly on top of enemy? (Seemingly random, but it's a question that must be answered.)

Combat Flow And Overall Sensation:

• Does the character move around as they attack and if so, how far? How does this change over the course of a combo?
• When are you permitted to attack: on the ground, in the air, in water, etc?
• What are you allowed to cancel your attacks with? (Determine this absolutely because this is huge. What you can cancel attacks with and when you can do it is oftentimes directly responsible for how challenging a beat 'em up feels, to say the least. Try everything.)
• Exactly how large are your attack hit boxes? The enemies?  (This requires a keen eye but is hugely enlightening.)
• What is happening to your character when you attack in the air? (This could be any number of things, every game does this a little bit differently.)
• Exactly what effects are playing during combat and when?
• What happens when you or an enemy is struck while in the air?
• As your attacks translate the character forward, what is happening to the enemies as they are getting "pushed on" by these attacks?

Combat Balance:

• What attacks/combos are utilized the most and why? (In fighting games, the mechanics that have the highest ratio of accessibility to usefulness are often referred to as "the bread & butter". It's important to evaluate the usefulness of these mechanics.)
• What attacks/combos are utilized the least and why? (One of the main problems with modern beat 'em ups is the huge amount of meaningless mechanics. Find out why they're meaningless and address it.)
• What is the usefulness of the given defense mechanics versus usefulness of the emergent defense mechanics? (What I mean is that oftentimes you are given a certain mechanic (i.e. a block or a roll) and it's usefulness is superseded almost entirely by a completely different mechanic.)

This is a pretty good idea of what I'm looking at when I'm playing these games. I know I forgot some or are not even considering some so please let me know what I'm missing so we can all be smarter about it.