The monsters we all remember the most clearly are those huge, beefy monsters that can both take and deal a lot of damage. Monsters that the encounter usually center around, and are usually a pretty difficult fight even on their own. These just outright try to kill the player (usually through stats), and take center-stage every time they appear. This category is the heavy; of course, named after the Team Fortress 2 class that wraps it up in a competitive multiplayer sense very nicely.
The first, most archetypal heavy is the Shambler from the first Quake. The first time the player runs into it, he can assume how dangerous it is because of its size, sound set and its overall design. It has the highest health in the game, and can do the most damage. As its ranged attack, it projects a stream of lightning for a few seconds that deals steady damage for as long as it’s connecting (you have to break line of sight to avoid it); dealing heavy damage if you’re caught in the full blast. Unless you have armor, its melee attack can potentially kill you in a single shot, as well. In addition to its high health, it’s resistant to explosive attacks, making it even tankier.
Heavies are kind of simple in how they work. Like the Shambler implies, heavies have to be able to both deal and take a lot of damage. There’s not much beyond that, in how their role works. It also helps if the heavy is competent in both ranged and melee combat; however, I’ve seen heavies that specialize in melee (Quake 4’s Light Tank) and heavies that specialize in ranged (Quake 2’s Tank, hilariously enough). Heavies are supposed to be intimidating, and having a heavy that’s useless at either ranged or melee combat lessens their impact unless they’re placed so that players are unable to take advantage of that (trickier than it sounds. It’s a good idea to grant your player enough respect to assume he’ll pull stuff like this).
Heavies by definition are a little bit like shockers. The player usually hates fighting them because they’re so dangerous and take so much punishment. However, there’s a major difference; heavies only shock by virtue of raw stats, most of the time. Shockers usually have some mechanic like some innate unpredictability, quick movement or things like that, but heavies are mostly just pure damage and high health. Also, once you learn how to fight them, they lose that shock value unless the situation makes its high damage and high health more immediate. Shockers are kind of required to stay shocky after the player understands them.
Quake 2 was another game that has a pretty decent lineup of monsters, and of course, it has heavies of its own. The Tank was its primary heavy-class monster. It took a lot of damage compared to other monsters (but some of the weapons almost-literally melted it), but it was practically a weapons platform. One arm is a machinegun, one is a reliable, decently-damaging blaster, and the other is a three-chamber rocket launcher. It was almost exclusively medium-to-long-range, and it had no melee attack of any kind. In fact, as I’ll discuss in a moment, it was really punished when the player got close.
The biggest point of the Tank is that it has so many attacks. It doesn’t just pull the same trick all the time like the Shambler does. Each attack has its own tell, and its own way of dodging. You had to duck under the sweep from the machinegun, dodge the blaster shot, and usually had to take cover from the rocket launcher. More than that, there’s another version of the tank you encounter towards the end of the game called the Tank Commander. It had a different color so the player could tell them apart, and a lot more health. Of course, the Tank was pretty much phased out once the Tank Commander was introduced. This kind of variety is good for heavies, because it keeps them dangerous. The Tank could be harder to deal with than the Shambler because it does different things than just the one attack, and the Tank Commander is good for refreshing it if it got stale (or would have been, if it was more different).
The Tank shows that heavies can work well as turrets, if they have a properly-designed attack for it. The three-chamber rocket launcher was great for bombarding an area if it was positioned correctly, and it was tanky enough that you won’t going to clear that obstacle quickly. The two roles aren’t really exclusive to one another, but I consider it primarily a heavy because it’s so much more dangerous than any other monster in the game (again, by virtue of high health and high damage). It does have one massive flaw that forces it to be used like a turret, however; if you got behind it, you had a few seconds where it needed to turn around to be able to attack you. If you were were quick, you could stay behind it and unload with the super shotgun, basically keeping it helpless. In my opinion, heavies shouldn’t have flaws like these, or if they do, they should be used in such a way that the player doesn’t have much opportunity to take advantage of those flaws. It really blunts the effect this role should have.
Heavies can also work as tanks (talking about the role. When I’m talking about Quake 2’s Tank, it’s with a capital T). The Brute from Dead Space is a pretty good example of this. It was a mostly melee monster, but had a ranged attack as well (not many people know about it, but I played around with the first one you run into and noticed it) letting it adapt to those situations. It could also close distances pretty quickly if you let it, and hit like a truck. It makes a good heavy in its own right, but what makes it a tank is that it has several thick plates in the front that mitigate damage. If you want to hurt it, you have to shoot it in the back, or hit one of the weak points near the shoulder (tricky to spot, but they’re there).
Heavies can work as tanks, by definition. Heavies sort of need high health in order to have the impact they want. When you add a gimmick like the Brute’s armor plating, you have a very effective tank as well. The difference, however, between tanks and heavies (and the reason I keep these two roles separate) is that heavies should be perfectly capable of killing the player. Tanks just need to get the player’s attention somehow so they can absorb damage, but they don’t have to actually kill the player themselves. Every heavy I can think of off the top of my head would be a decent tank, but not every tank would be a good heavy. Red Faction: Armageddon’s Monolith isn’t, for example.
The problem with the Brute, however, is a problem I alluded to with Quake 2’s Tank. With Dead Space’s limb-severing mechanic, you can kill them very easily. If you know where to shoot and are fast enough, you can take advantage of the gaps in the Brute’s armor and pick it apart with the game’s first weapon! Even if you know how to fight them, the Shambler and Tank (ignore its turning speed for a second) can still be difficult fights. As I said before, heavies shouldn’t have flaws like this, or if they do it should be done in such a way that the player can’t take easy advantage of it; otherwise the effect the heavy should have is lost.
The Hercules from Binary Domain lets me make one extra point that I found interesting. As a heavy, it was pretty standard; it took a lot of damage, it had a large chaingun that ripped right through you, and it was very, very obvious in a fight. It wasn’t encountered often (aside from a few rail-shooting segments), as well.
What was interesting about them was another monster entirely. There was one support monster you encounter throughout the game called the Whirler. All it did was ferry individual fodder into the fight. About half-way through the game, though, we see flying Hercules’ being kept aloft by Whirlers, making the Hercules a pretty different fight, though we immediately know what to expect because we have seen both monsters before. While it was a concept that was only really hinted at in Binary Domain and I haven’t seen it fleshed out anywhere, heavy-specific supports (supports that only exist to support heavies) would be very good to see somewhere.
Heavies are pretty straightforward in how they’re balanced. You’re trying to make a monster that absorbs and deals a lot of damage, so make sure it absorbs and deals a lot of damage. When you’re making a monster that tries to actively kill the player, there’s a trap a lot of people fall into where they design it in such a way that it does it too well. The attack does too much, it’s too difficult to dodge, etc. You always have to give the player some way of defeating it. If your goal is to kill the player, put him in a crusher as soon as the level starts. The goal here is to challenge the player and provide an enjoyable game. Once you have that in mind, balancing them is easier than other roles, like shockers and supports.
One more thing I have to say, however, is about heavies with specific vulnerabilities. The Strider from Half-Life 2, for example, was only vulnerable to explosive weapons, and even then it took a lot of rockets to bring down. What ends up happening if it’s outright immune to your other weapons is that you have to make sure that the player has more than enough of that high-power ammo to bring it down. Otherwise it gets really frustrating for the player (and indeed, that first time you fight them in Half-Life 2, it was). In order to balance the large amount of ammo the player needed, they made sure the rocket launcher couldn’t carry much ammo and placed crates that give you infinite rockets, so you had more than enough for that boss fight, but didn’t have enough to outright break other encounters. However, if you go through all that trouble for just the one monster, it’s not really a heavy anymore, it’s just an outright boss encounter.
The heavy is a role that has been around since the beginning of the shooter genre (the SS in Wolfenstein 3d), and is one of the central roles you can find in most of them. Even modern-military shooters could feature a heavy in some form because of how simply they work. They’re also one of the easier roles to balance correctly. Like shockers, they have a tendency to evoke that reaction from the player, and convey a feeling that a big battle has just started.