Tag: metroid fusion

In honor of Spook month, I wanted to analyze the design of Metroid Fusion‘s arguably spookiest boss, Nightmare. Certainly a spooky name. I’m fascinated by gameplay that leaves a lasting impact on people, experiences that are remembered long after the game’s last play session. Nightmare seems to be one of those special few bosses that everyone remembers, if they’ve played the game he debuted in. There’s something viscerally haunting about Nightmare in particular that sticks with you. In a game full of terrifying encounters with predatory aliens on an isolated space station, he manages to stand out as this weird, horrific science experiment gone wrong.

In Metroid Fusion you play as galactic bounty hunter Samus, once again finding herself in the unenviable position of being trapped in isolation with ravenous alien monsters that want to eat her face. Unfortunately for them, wanting to eat Samus’s face is the leading cause of death in the Metroid universe, so the player and Samus will team up to claw their way through the abandoned space station to recoup Samus’s gear, destroy the monsters within, and blow the place to kingdom come.

To give a quick rundown of Samus’s capabilities, for those who have not played Metroid Fusion, Samus primarily does a lot of running, gunning, and jumping. Samus can jump high into the air and, at this point in this game, perform the space jump – where she can gain extra height in mid-air as much as she likes, so long as the jump button is pressed just as Samus begins to fall from the previous jump. Think a standard double jump, except with no limits. An infinite jump, a space jump, if you will. She can make herself a smaller target by curling into the morph ball form, with which she can also roll around in tight spaces. Samus can shoot horizontally in basically any position except the morph ball form. She can also aim vertically while standing or jumping, but diagonally upward or horizontally while running as well. Her primary weapon is a beam that can be charged up while moving then released for extra damage, and she has a limited stockpile of missiles she can fire in place of her beam. They do about as much damage as a full charged beam, but have expendable ammo.

It’s hard to describe what exactly Nightmare is. He’s some sort of awful military experiment with gravity manipulation. It a bio-mechanical monstrosity hooked up to a gravity device, and perhaps some sort of life support apparatus, sealed within with an ominous mask. He has very limited animation, with basically only a few details on his arms and *ahem* face to distinguish him. He kind of just stares in one direction and floats around, but visually it works because of the kind of character he is. He’s pretty horror-themed, with his thousand yard unblinking stare and immovable stance in one direction reinforcing this sort of awful, emotionless terror-machine.

The Nightmare boss fight is made up of three distinct phases that seamlessly transition from one to the other linearly as the Nightmare creature takes damage. As is often standard for 2D action games, Nightmare’s behavior pattern is actually rather simple once you break it down. In the first phase, Nightmare will only do two things. First, he’ll fire a salvo of laser projectiles that move horizontally in a line from his arms. Several are fired at once, forming an obstacle that is just high enough for Samus to be able to jump over, if they’re fired near the ground. This is complicated by the second thing he does; he will track Samus’s vertical position with his own, levitating up and down to match her “y” position on the screen. It’s not one-to-one though, Nightmare overshoots Samus’s position, and if she quickly changes her vertical place, Nightmare will have to take a moment to reorient itself as a result.

This movement creates the sense that Nightmare is an intelligent predator going out of its way to aim its deadly lasers at Samus, although in truth they aren’t aimed as such. Nightmare is repositioning its entire body to fire at Samus. This overshooting vertical motion is a simple and effective way to convey the illusion of intelligence in enemy AI. An enemy that perfect lands its shots every time, with no room for error is even simpler to implement, but it’s not very satisfying to fight against. By having Nightmare overshoot, he seems more alive, with the capability of making error, while staying motivated and on target – he tries to shoot Samus, but does not do so perfectly. Once the player can properly manipulate Nightmare’s movement, they can defeat him much more easily. One could even say that Nightmare’s movement is an extension of the player’s own as Samus. It’s always a response to how she moves, that is then disrupted by the lasers which fire on their own time, beyond the player’s control. Having mechanics interact like this instantly multiplies the number of situations that are possible, and this simple interaction alone drives the entire first phase of the fight.

There’s one more complication, however. Nightmare is immune to Samus’s weaponry on most of his body, vulnerable only at one specific weak point – his gravity device. Dodging Nightmare’s attacks in the first phase is not a terribly daunting task, as again his movement is totally lead by Samus. The position of his weak point forces you to try to manipulate him in a certain way, though, and this may put Samus in harm’s way. It’ll be easier to understand how this work by understanding how Nightmare is shaped:

As you can see, Nightmare is made up of these four primary parts, very approximately outlined here. None of the areas marked in green can take damage, but the red gravity device can. So now first phase is a game of landing your shot in that small space between his arms, which will otherwise block your fire. Seems difficult, but is thankfully alleviated somewhat by a beam upgrade Samus will have by this point in the game, which makes her shot very wide, so damaging Nightmare requires a precision, but not pinpoint precision shot from Samus. This also means hitting Nightmare is much easier with the charge beam than with missiles, ensuring the player is taking some time to charge up, and therefor interacting with Nightmare’s attack pattern as the fight goes on, none of his mechanics can go ignored. To access this weak point, Nightmare needs to be high enough in the air, and thus the ladder on the back wall Samus can use to goad him into exposing himself. This little scenario will also give the player ample time to observe and learn about how Nightmare’s movement works. If the player can successfully repeat this cycle a few times, Nightmare will activate his gravity field, and we enter phase 2.

Nightmare’s gravity field makes Samus heavier, causing her jump to get a lot less airtime, and her running movement to be a lot slower. At the same time, Nightmare will be encroaching on Samus slowly, characterizing a very off-kilter and haunting vibe. Nightmare does not track Samus’s position here, but rather simply bobs up and down a short distance. This happens rhythmically and regularly. He notable stays in his higher position for a longer time than his lower position, designed such so that the player has time to aim a beam shot at the gravity device. His lasers now fire only two at a time, so Samus’s shorter jump can clear them, but they follow their own regular timer that is desynched from Nightmare’s movement, meaning they can fire at any vertical “Y” position, so the player will have to duck or jump the lasers on the fly. This shift to a more reaction-focused mechanic reinforces a sense of being on the backfoot, of the terrifying creature closing in you, literally forcing you into a corner.

The method of attack remains the same here, but it’s re-contextualized, as Nightmare now moves of his own accord, meandering around like a zombie, rather than following your lead. He reminds me of a horror-movie monster, the way he sort of just vaguely shambles toward you. The fight remains simple, but the distortion of the environment, the ooze dripping from his eyes, and the ominous humming of his gravity device, along with the subtle shift of the mechanics toward reaction-based gameplay really sets the mood. The aesthetics do a lot of work here, creating a building tension going into the third face, er, I mean phase, which starts with..

HOLY mother of god what IS that!? Augh, yes his mask comes off to reveal this grotesque melting abomination once you’ve destroyed the gravity device. At this point Nightmare will gradually move toward you, firing lasers in a new much more aggressive pattern, forcing Samus off the ground. If Samus tries to jump over Nightmare, he will fly off screen then back on in an attempt to ram her. Nightmare is responding to Samus’s movements again. It’s more obscure and aggressive, but still predictable. Once you understand that bosses like Nightmare are only responding to their circumstances (aka you, The Player), you can predict how they’ll react and use that to your advantage, and this applies to pretty much any AI enemy. Incidentally, this is largely how competing against real people in games works, too, although they might be a bit smarter than Nightmare. At any rate, he’s now vulnerable to missiles, so blast his exposed face to smithereens. It’s a lot easier to damage him in this phase, so it’s simultaneously cathartic as his increased aggression continues to build tension. The extra room and freedom to move about more of the arena creates a sense of a shift in tone. Samus is now in a position of greater power, and Nightmare a position of greater desperation, to match his screeching unmasked face.

It’s worth going over here a kind of ‘soft’ phase 4 for Nightmare. Nearly every boss in Metroid Fusion, once defeated, releases its Core X, a parasitic creature that contains some of their power. Samus must defeat this as well, before she can breathe a sigh of relief. The Core X is a pretty simple floating target that can be taken down with a few missiles. Beam attacks don’t damage it, but they do release some health and ammo restoring items. The Core X’s behavior is to simply follow Samus’s current position, and move towards her to ram her. You’ll notice it uses that same ‘follow but overshoot’ technique Nightmare employed, except in both the horizontal “x” and vertical “y” positions. If you know to look for it, you’ll see this mode of movement in AI design everywhere. I always found these Core X encounters a very interesting kind of denouement to boss fights, where there’s still some danger, but not nearly so much, as the heightened tension eases out. It’s a pretty satisfying cap off to hard encounters, and not many games do anything similar. It’s unique.

It seems to be the case that Nightmare’s design is intended to exercise all of Samus’s mobility options. The presence of a ladder on the back wall gives the player easy access to the air above Nightmare for some evasive space jumps, certain Nightmare attacks are best evaded by Samus’s famous morph ball, and a command of Samus’s ability to fire diagonally while moving gives a huge advantage in this fight. Nightmare is one of the first bosses in Metroid Fusion that really pulls together a lot of Samus’s various capabilities, and, even though he’s rather simple and straightforward, he does a great job of it. He marks the beginning of the endgame sections of Fusion, and can be a bit of skill check for people, so they may very well get stuck on him for a time. This coupled with the outstandingly horror-filled atmosphere that follows from his horrific design, reinforced by AI behavior reminiscent of a lumbering horror villain, and you’ve got a recipe for an extremely memorable encounter.