So that’s Metroid done the right way. Part of what makes Metroid so fun, though, is the way it lends itself to being played the wrong way. Like a lot of games at this sort of mid-grade 8-bit technology level, Metroid contains a fair few glitches and bugs that don’t render the whole thing unplayable but rather make it more interesting. Metroid‘s underpinnings are complex enough that some things don’t work quite the way they’re supposed to, but simple enough that when the game goes looking for elements in the wrong part of memory or whatever it can still keep plugging away… albeit in a manner the developers never intended.

You see the same thing in Super Mario Bros. and Pokémon Red/Green/Blue as well. Unlike contemporary games, which are complex enough to contain advanced bug-checking filters or else simply fall apart when something goes wrong, Metroid bounces back when you hit it with unexpected data. It keeps on truckin’. As such, some of Metroid‘s glitches have become legitimate elements of many players’ arsenal.

A lot of Metroid‘s instability comes from the developers’ determination to push the NES hardware in never-before-seen directions. You can see the game struggling to keep up in the course of normal play; discolored scenery like this, for example, reportedly comes from the program code attempting to render scenery faster than it’s properly able to keep up with, meaning that when you dash into a new area or plummet down a shaft at full speed, the game struggles to keep up and eventually just says, “Well, good enough.”

Also unique to Metroid are a number of odd little game design oversights that the creators either didn’t catch or didn’t have time and resources to clean out before launching. For instance, one of the best-known quirks of the game is the way enemies, which normally are contained within the rooms in which they spawn, can be drawn into open doors at the same time as Samus’ transition from one room to another. Normally, this is a nuisance, since she remains vulnerable despite the player being out of control of her actions — meaning she takes unavoidable damage during what should be “down time.” But in some cases, you can do weird things.

For instance, you can lure standard enemies into boss battles. This doesn’t have any real impact on the game, but there’s a certain charming novelty in seeing a Waver or Reo flutter around while you’re blasting Ridley point-blank in the groin.

Of much greater value, however, is the ability to lure a Reo into the statue room immediately after acquiring some Missiles and the Bombs. Blast open the red door at the upper-left corner of Brinstar, pull a Reo into the room as you head left, and get it to fly down into the lower portion of the room and into the water/acid/whatever. Freeze it while it’s at the water’s surface, do a bomb jump off its back, and you can roll into Tourian long before you should be able to. This is a key tactic in a lot of speed runs of the game, although you’ll probably get pasted by Tourian’s hazards pretty quickly if you try doing this outside the confines of a tool-assisted playthrough. Still, it’s there, and that’s rad.

The bomb jump factor, of course, is another part of the game — an exploit that actually could be intentional. Because the explosion of a bomb propels Samus slightly upward and she can drop multiple bombs at any given time, you can harness this element of the game physics to allow Samus to “ride” the crest of sequential bomb explosions upward. With the proper timing, there’s actually no limit to how high she can reach provided she doesn’t hit an enemy… though it takes a steady hand to sustain a bomb jump for long.

Curiously, bomb jumps seem to be a specific feature of the NES version of the game; I’ve found ports like the 3DS Virtual Console rendition of Metroid, despite being ostensibly accurate to the original game, make bomb jumps vastly harder to pull off. I don’t think this is a deliberate action on Nintendo’s part to quash the exploit, though. More likely it’s simply a matter of the different hardware and interface timing.

As a corollary to the bomb jump, Samus can also use a related technique by exploiting the fact that bombs propel Samus regardless of her pose at the time of the explosion and the fact that she can jump from her “neutral” animation frame. Drop a bomb and immediately stand up, and when the bomb explodes it will send Samus flying upward slightly without changing her pose. This means you can jump in midair (years before the Space Jump!) and reach areas that might otherwise have been slightly out of reach.

Of course, the greatest technique of all is the wall climb skill, made famous by the Nintendo Fun Club Newsletter. An arcane combination of the behavior of blue doors — they seal back up a few seconds after being opened — along with the way the screen centers on Samus’ position and the physics of rolling into Maru-Mari form allows you to “climb” to new areas. When a door closes over Samus, she effectively becomes lodged in the scenery, though since she’s rendered immobile the only thing you can really do when trapped in a door is shoot it open again… or roll into a ball.

If you simply roll into a ball, well, you’re screwed. The bombs won’t open a door, and you can’t stand back up. But if you immediately stand after ducking, something about the animation makes it possible to rise again — and not only will Samus stand, she’ll actually be situated one block of the wall higher than before ducking. Repeat this rapidly and Samus will slowly climb the inside of the wall and off the screen. However, if you tap jump rapidly, her attempts to leap will cause the screen to slowly readjust to place her at the center. With an alternating combination of ducking/standing actions and rapid jumps, Samus can climb any vertical chamber.

This has incredible value in certain areas; I used it in my playthrough to reach the Varia long before I had the Ice Beam and High Jump. In others, it can be deadly. You need to reach another blue door in order to escape the wall, so if you climb a room with no door in the wall above your starting position, well… that’s a shame.

But it’s also possible to go into Metroid‘s equivalent of Super Mario Bros. “minus world” — areas above the actual boundaries of the current map. Here, you may be able to find shafts that shouldn’t exist, rooms that beckon for exploration, strange mishmashes of graphics and color palettes, and more. Most of the time you’ll simply reach a dead end and die, but until fans at sites like Metroid Database sorted out the particulars of Metroid‘s “secret worlds” and determined that they were just buffer overflows and misplaced data pointers, many speculated that the creators had hidden away deliberate secrets — new areas to explore, additional goodies to acquire. But, no.

It doesn’t matter, though. Metroid‘s oddities and errors have become an integral part of its legacy — unintended features embraced by fans. While sequels smoothed them out one by one, the series’ stewards have paid tribute to this part of Metroid‘s heritage in various ways… perhaps most notably with Metroid Fusion‘s dead-end “shinespark” sequence break.

And… that’s it for Metroid. I’ll be hitting the sequels, eventually, but next up: Something very different… but somewhat related.

With the Mother Brain defeated, Metroid ends up back again where it began. The final sequence of the game doesn’t involve combat or exploration but rather a tense escape sequence up a seemingly endless shaft — an echo of the game’s first sprawling vertical area, the one that definitively set Metroid apart from a legion of left-to-right side-scrollers.

This is no straightforward reprise, however. That early tunnel was a teaching experience, helping players come to grips with Metroid‘s unconventional design. A host of patrolling enemies imparted the value caution, while the seemingly unending upward scroll instilled patience and persistence. The wide platforms didn’t simply force players to navigate by zig-zagging horizontally within the ascent, they also provided a sort of safety net in the event of a slip-up. You might fall and lose some progress, but not much.

This shaft, on the other hand, affords no caution. It lacks enemies of any kind — after all, Mother Brain is dead, so what’s the point? — but that doesn’t make it easy? Samus is racing here to escape the Zebes underground before the space pirates’ spiteful self-destruct countdown ends, giving you roughly 90 seconds to make the climb and escape.

This is much more easily said than done, however, because the shaft contains only itty-bitty platforms. The only surfaces in the game smaller and more precious than these tiny things are those three single bubbles floating in a line deep inside Norfair — and the worst thing that could happen if you missed one of those is that you’d fall into lava and lose a bit of health. A single slip here is likely to send you plummeting all the way back down to the start. You can only afford a couple of minor slips before you’ve wasted so much time there’s no hope of reaching the end.

The escape sequences tests your understanding of Metroid‘s physics like nothing else in the game. For most of the adventure — especially since acquiring the Screw Attack — Samus’ aerial summersault is one of the most important and powerful skills in the game. But here, it’s absolutely deadly, because she’s much harder to control once she starts spinning.

To survive here, you need to fight your programming and resist the urge to spin. By leaping straight into the air, Samus will remain upright and follow a much tighter arc with her jump. This means you have much less lateral range when you leap, but the platforms here are arranged in such a way that you don’t need to move much to either side. After hours of wild, weaponized leaps, the secret to survival is to move cautiously and deliberately, employing the full range of Samus’ skills.

Once you get the rhythm down, this sequence turns out to be remarkably easy. Keep your nerve and move with care and you’ll reach the top of the shaft and escape to freedom, where you’re visually graded on your efficiency. Take too long to beat the game and Samus turns her back to you in despair; play quickly enough, however, and she reveals her shocking (in 1986) secret: A feminine pronoun. Play even more effectively and you’ll be able to control Samus in her unarmored female guise.

Play really well and she’ll strip down to a tiny two-piece bikini for some 8-bit titillation. Nintendo was pretty progressive, making Metroid‘s protagonist a woman, but… well, baby steps.

No, you can’t play as bikini Samus. No matter how much you wanted to as a 13-year-old.

Now that I think about it, Metroid kind of did the New Game + concept, huh? Once you beat the game, you can start over with every item and power-up in your inventory save Missiles and Energy Tanks. The alternate character sprite is a sort of hidden bonus to reward players who try to make better time through the game by improving their time in subsequent cycles, but the simple fact that you can start from the beginning with both a more powerful character and a clear sense of the labyrinth’s layout is enough to motivate some players.

On the whole, this trip through Metroid honestly surprised me. I think I’ve bought into the general sentiment that it’s a clumsy, dated, badly made, and nigh-unplayable mess — but really, that’s not true. Certainly Metroid has its rough spots, and you can definitely see the limits of both 1986′s technology (in the glitches and repetition of scenery) and game design (in the poorly communicated mechanics throughout the middle stretch of the adventure).

Yet on the whole, Metroid‘s powers and world are at once inventive and effective. The fact that the tools to range further into planet Zebes are integral parts of Samus’ arsenal rather than standalone keys really sets Metroid apart even now. The idea of exploration expanding organically as a function of the protagonist’s growing skills is one of the most compelling forms of game design in existence, and I think it’s safe to say that Metroid didn’t just pioneer it — it nearly perfected it in one go.

Nearly. The game does have its flaws, no doubt. But think back to the first portions of the game, the way it’s so deliberately structured to guide you to the items you need while holding you back from areas you’re unable to deal with — that’s some remarkably mature and sophisticated game design. I really feel like game design truly came into its own in the second half of the ’80s, and Metroid was one of the key titles that helped lead the way. Maybe it wasn’t amazingly revolutionary on its own, but as part of a larger movement toward more complex and sophisticated design, it deserves a place in history.

Plus, it set the framework for Super Metroid. That alone makes it worthy of admiration.

Tourian is as close as Metroid comes to having “levels” in the traditional video game sense. You make it through the gauntlet of Rinkas and Metroids a screen at a time and arrive at last at the boss. Even the doors in Tourian say “serious business” — they’re orange instead of red, soaking up ten missiles instead of five. The only other door in the game like that was the one behind Ridley. The message is clear: Every time you reach a door in this area, you should experience the same sense of elation you feel when you’ve just beaten a boss.

Behind the final door, the boss room awaits. And, you know, the idea of a “boss room” has become a real cliché in games. Even here in Metroid in 1986 we saw both Kraid and Ridley situated in strange, stark chambers where they did nothing but sit in wait for the hero to come blow them up. It’s kind a goofy concept if you stop to think about it; how miserable must that existence be, lurking in the dark with nothing to do until some do-gooder comes along to blow you up? You never see proactive villains in action games like this — though this very franchise made a brilliant and terrifying exception to that rule in its fourth installment — just slobs who sit and wait until the good guy finally gets through the deadly-but-not-too-deadly gauntlet leading up to them.

In Mother Brain’s case, however, this actually makes perfect sense. She’s a biological computer, and as such this is basically her server room. She’s totally immobile, powering Zebes’ systems or whatever from the safety of Tourian’s deepest sanctum, just like you’d expect a computer to do. And what she lacks in direct firepower — the Mother Brain is completely harmless unless you bump into her — she makes up for with supporting defenses.

Mother Brain’s lair is a single lengthy room divided internally into six different chambers by five Zebetites, which appear to be conduits or defensive barriers or something. Like Mother Brain, they’re biomechanical, meaning they possess regenerative capabilities. Each one takes several missile blasts to destroy, but if you don’t pour on the steady fire they quickly grow back — you can gauge your progress, not to mention the ground you’ve lost, by the condition of a Zebetite. They start thick and slowly dwindle in diameter to vanishing as they take damage, growing back to full width if you don’t destroy them quickly.

Like Mother Brain, a Zebetite also can’t attack you directly. However, taking them out is anything but a cakewalk, because each one is elevated high off the ground with only a narrow platform adjacent to give Samus a clear shot. The problem is that while you’re doing this a trio of guns is rotating and firing energy beams at you in a not-quite-random fashion. And, on top of that, Rinkas are spawning rapidly from every direction.

Despite the final boss’ lack of a direct threat, this is an extremely challenging sequence. Taking down the Zebetites burns through your stock of missiles quickly, and because Rinkas don’t drop energy pickups and Metroids only respawn when you die and continue, you’re stuck fighting with what you have on-hand. [Edit: Or maybe I'm wrong about this, but still -- tough sequence regardless.] It’s a battle of attrition, a test of how effectively you can dodge the threats surrounding you and pour missile fire into your targets. The developers do demonstrate a surprising touch of mercy here, though: Once you destroy a Zebetite, it’s gone forever. Like the minibosses, Mother Brain’s energy conduits don’t regenerate if you see a game over. In a worst-case scenario, you can fight your way through this chamber one Zebetite at a time, constantly restarting and fighting your way back, delving a little further into the room each time.

The further you get into the room, the more difficult it becomes. Around the time you hit the lava, it just gets ridiculous. Don’t computers need cold to work more efficiently? Shouldn’t Mother Brain’s server room be, like, super refrigerated? Pfft.

Really, this room can be as difficult or as easy as you like. The gun turrets follow fairly predictable patterns — some shoot at 90-degree angles, while others fire 45-degree-angle shots — and while the Rinkas materialize from all over the place and home in on Samus’ location as of the second they spawn, they obey the same strictures as they did during the Metroid gauntlet. Specifically, there will always be a fixed number of them on-screen at any given moment, so if you freeze one it’ll take that particular spawn out of play.

It’s actually not too difficult to deal with the Rinkas while destroying the Zebetites, because each column has solid footing directly below it that allows you to skip the blue platforms and jump up and down right in front of the Zebetite, firing several point-blank missiles per leap and wearing down the Zebetite in short order.

Mother Brain herself, however, is considerably more difficult. Once you shoot out the glass case surrounding the computer, you need to pump more than 30 missiles right into her face (and they have to hit dead-on or they won’t cause any damage). Unlike the Zebetites, her health doesn’t regenerate if you lay off your assault for a moment. That’s about the only saving grace, however.

The most sensible place to attack Mother Brain from is the Zebetite junction directly in front of her — the blue platform further away works as well, but it’s constantly targeted by both Rinkas and gun emplacements — yet this leaves you incredibly vulnerable. Rinkas spawn constantly above and below you, and if you’re hit there’s an awfully good chance the recoil will send you flying into the lava directly in front of the glass chamber. The wall to the right is slightly too high to reach while jumping out of liquid, and if you try to use Mother Brain’s platform as a foothold you’ll take damage from proximity to the boss and be sent flying right back into the lava. The only reliable way out is to freeze a Rinka and use it as a foothold, but that’s pretty difficult while you’re being harassed by several others at the same time. The moral of the story: Don’t let yourself be knocked into the lava.

Because there’s no time crunch here, the smartest thing to do is to take your time. Drop back and freeze the Rinkas, giving yourself a short window of breathing room. But this tactic is slightly counter-intuitive to the design of the entire room; because the five Zebetites leading to Mother Brain required a rapid volley of missiles, your brain is still in “frantic” mode when you finally reach the boss herself. You actually need to stop and recalibrate your approach here.

With smart play and the good sense not to fall in the lava, you can eventually best Mother Brain… even if you have to keep dying and retrying to do it. But once that happens, the absolute trickiest part of the game begins.

The player’s arrival in Tourian (the final zone where the Mother Brain awaits) is accompanied by a shift in tone. The visuals are stark and mechanical, a contrast to the natural formations and ancient constructs of the rest of Zebes’ underground. Even more strikingly, the background music ceases to be musical and instead adopts the dissonant sound of random computer noise. Clearly, this space represents the enemy’s true lair, a futuristic expansion on the existing natural labyrinths designed for the cybernetic enemy leader. The message should be clear: “This is it.”

Once you step off the elevator into Tourian, another difference makes itself apparent. This zone contains neither minor enemies nor any need to explore. It’s a totally linear path to the end, and only two kinds of foes appear: The small energy toruses called Rinkas, and the creature from which the entire franchise derives its name, the Metroid.

Metroids represent a different kind of enemy than has appeared to this point — not just for this adventure, but for games as a whole. The closest contemporary analogue I can think of is Ghosts ‘N Goblins‘ Red Arimer: They’re smart, aggressive, fast, and utterly deadly. Unlike the other creatures that populate the corridors of Zebes, Metroids don’t waffle around with fixed paths or aimless meandering that makes a minimal sort of effort to drift in the direction of Samus. They lurk in wait at fixed points, and the instant Samus comes into their range (coincidentally, this range is marked exactly by the edge of the screen) they dart forward quickly to attack.

As for their attack, they don’t settle for simply bumping into Samus and knocking x number of points off her health total. Instead, they latch on like parasites and begin draining her energy. A Metroid is never sated, so it will cling to Samus until she’s dead. Up to three Metroids can appear on-screen at once, some more aggressive than others, but all intensely dangerous. The one upside to Metroids is that the the health and Missile refills they drop are worth several times as much as normal refills… though even with the Varia, enemies here hit for 15 points of health, so it can be tough to keep ahead of the power drain once Rinkas appear. Heck, the first one to materialize actually spawns as Samus is passing through a door and hits her while she’s locked in a screen transition — a free hit just to say “screw you.”

Once you descend a few rooms into Tourian, the Rinkas start to appear alongside the Metroids. They spawn infinitely from various points around the room, and the screen always has three at a time. Like Kraid’s spikes, you can freeze them to take them briefly out of play; if you destroy them, another will immediately respawn to take its place… and there’s always a chance it’ll respawn directly under Samus’ feet, meaning it’s much less dangerous to simply freeze them. That’s more easily said than done when Metroids are closing in on you, though.

What makes Metroids particularly dangerous is that they only have a single weakness: Ice. (Later games explicitly call out their vulnerability to cold, meaning any possibility of hand-waving the improbable physics of the Ice Beam’s freeze effect as zero-point gravity or stasis or something is right out… not that it matters in any way, shape, or form.) You can push a Metroid away with Missiles or the Wave Beam or the Screw Attack, but these weapons don’t actually harm the creature. Only by freezing it does it become vulnerable, and only then to five Missiles.

So, the strategy for this area becomes fairly straightforward in concept: Inch forward to lure a Metroid from hiding, freeze it, pump it full of explosives until it dies. Dodge or freeze Rinkas when necessary. Repeat. This is more easily said than done, however, given the high speed and unconstrained motion of the Metroids. They can attack from any angle, swooping in from above or below in a split second to latch onto a tasty Samus-snack. And you’re often descending vertical shafts into Tourian, meaning they’re coming up from beneath you and hovering hungrily beneath your feet, a tiny platform the only thing separating Samus from safety and a brief future of shriveling into a dusty husk of former humanity.

Metroids “pace” beneath you, drifting slightly back and forth until they get a clear shot, a behavior you can exploit to lead them up as you back away and line up a clean shot. Thankfully, when a Metroid latches onto Samus, it briefly moves down to her level to line up its mandibles or whatever, so you have a brief instant of contact in which you can freeze it before it surrounds you. If you’re too slow, however, the Ice Beam becomes useless. When a Metroid begins draining Samus’ health, she can only run back and forth while waiting for the inevitable. The only way to dislodge a Metroid is to duck into a ball and lay down some bombs, then roll over them and hope the angle of the blast knocks the creature free. This gives you only a sliver of a reprieve, however, as the Metroid will be stunned for a fraction of a second before shaking off the blast and moving back in for another nibble. This gives you just enough time to stand and freeze it.

Metroids create a harrowing sensation like nothing else in the game, especially once they start to appear several at a time. Until you know the trick of defeating them, they’re utterly baffling in their sheer deadliness and persistence. Their intensely aggressive nature combines with their unique life-sapping properties to create a wholly unique kind of foe. According to designer Yoshio Sakamoto, the name “Metroid” comes from “metro” (as in subway) and “android” — that is, the robotic-looking Samus is exploring underground tunnels like a subway. But it’s wholly fitting that the game’s creators gave these distinctive foes the name, because they’re far and away the most frightening and dangerous aspect of the adventure.

It can be a shock of cold water to go from aimless exploration in low-threat environments to a final run-up through Tourian’s brutal Metroid gauntlet, but this area forces players to use both their wits and all the combat skills they’ve picked up along the way to survive.