The World Design of Metroid Prime 2: Echoes | Boss Keys

Given the success of Metroid Prime, a follow-up was inevitable. But developer Retro Studios didn’t want to just make a simple sequel: they wanted to make something completely new. So Metroid Prime 2: Echoes, released two years later in 2004, has all new areas, fresh abilities, brand new characters, and even brings in old Metroid features that got cut from Prime, like wall jumps and the Screw Attack. But some of the biggest changes to the game are in relation to exploration of the game’s interconnected world.

Which is exactly what Boss Keys is all about: looking at how Metroidvanias get made, by breaking down the world design of some of the genre’s landmark titles. So, perhaps the most fundamental change from Metroid Prime 1 to 2, is the fact that the game’s world, Aether, is split up into distinct chunks. Agon Wastes is a rocky, semi-industrialised desert. Torvus Bog is a soggy wetland, with a secret flooded basement. And Sanctuary Fortress is a striking sci-fi stronghold, built high up among the cliffs.

They all connect to the Great Temple, which acts as a sort of hub world. And the areas eventually connect to each other, as well. And, sure, Metroid games have had distinct zones before. Like Norfair and Brinstar in Super Metroid. Or Phendrana Drifts and Chozo Ruins in Metroid Prime. But Prime 2 really commits to this idea. The game asks you to go to each area in turn. Then you’ll stay there for a few hours as you explore, find power-ups, collect keys, and fight a boss.

Then you leave and, for the most part, you don’t come back. All of which makes these areas feel a lot more like Zelda dungeons than Metroid areas. They’re even referred to as temples, just like Zelda. And, you know, I think this is actually quite a good idea. One of the biggest challenges of Metroidvania design is that it’s simply not very fair to ask players to remember an entire world map, across a ten, twenty-hour experience.

By the end of a game like Super Metroid, the explorable space has grown so enormous that finding the way forward is a truly daunting task. And if you leave the game for a couple days, you’ll be completely lost by the time you go back to your SNES. And so by busting Aether up into self-contained bits, the player can focus on one area at a time. You just need to think about Agon Wastes. Then you can offload that entire area from your memory and focus on Torvus Bog.

Then you can forget all of that and just think about Sanctuary Fortress. Or, you would, if it weren’t for two annoying moments where Prime 2 breaks this pattern. So, after getting the Boost Ball in Torvus Bog, you actually need to leave the bog and go back to the front door of the dungeon, which is in the great temple. Now you can use the boost ball to rocket up this half pipe and find a path to the Seeker Missiles. There’s something more annnoying in Sanctuary Fortress, though.

The first item we get is the Spider Ball and while there are a few places to use it in the Sanctuary itself, they all lead to dead ends: maybe a useful upgrade, but nothing to actually progress our adventure. That’s because the path forward, to get the Power Bomb, is actually back in the Torvus Bog. Right down at the bottom of the temple, in a room just off from where we fought a boss, there’s a forgettable Spider Ball track that leads to that all important new power up.

To continue the Zelda metaphor, that’s like getting the hammer in the Fire Temple, and then realising that you now need to leave the dungeon, travel across Hyrule Field, and go back to the boss room for the Forest Temple to actually use your hammer. It wouldn’t make any sense. So that item order chart actually looks like this. And these were the only two times in Prime 2 that I got stuck. And bear in mind, that I’m playing these games with the hint systems turned off.

Because for the most part, Prime 2 doesn’t ask you to revisit old areas. Sure, the game would reward players who did remember those previous temples. For example: After you get the seeker missiles from Torvus Bog, you can use them to open a door in Agon Wastes and unlock the Darkburst: a powerful, and completely optional weapon. But the Seeker Missiles and Power Bombs are the only mandatory items in the game that are found outside of the current area.

And I feel like that breaks a fundamental promise that Metroid Prime 2 is making. Suddenly it goes from asking you to remember a single zone - to asking you to recall hundreds of rooms across an entire map. Okay. So one other advantage of breaking the world up into smaller chunks, is that it would theoretically allow Retro to make these areas more complex - because they’re only asking players to get their heads around a single area instead of a whole map.

And, in some ways, that’s what happened. For example, the areas are still very linear in how you finish them, with a predetermined order to the power-ups. However, there are also these three keys, which open the boss door, and you can get them out of order. That adds a bit of extra challenge and non-linearity to your exploration. And then there’s the other massive change for Prime 2: the Dark World. So, again taking cues from Zelda, Prime 2’s Aether is split into two, with each area in the game having a corresponding “Dark World” variant.

Light Aether is bright and relatively safe, but hop into a portal to Dark Aether and you’ll find a world that is claustrophobic, crawling with enemies, and teeming with low level radiation that will eat away at your health bar unless you’re standing in these bubbles of light energy. It’s seriously quite spooky, and before you’ve got the Dark Suit, which makes you way more resilient to the radiation, there’s a real experiential shift when you jump between the two zones.

But how does it affect exploration? Well the main thing is that often your path through the Light World will be blocked. so you enter a portal into the Dark World, make some headway there, and the find another portal, back to the Light World, taking you past the blockade. Ehh, it’s kinda cool - but rarely a big head-scratcher. But then there’s this. Soon after the portals are introduced, we find this locked door, and see that the controls to open it are only present in one version of the world.

We need to activate the lock in Dark Aether, to unlock the door in both versions of the world. So this sets up interesting possibilities for puzzles, where affecting one version of the planet has ramifications for the other half. Stuff we’ve seen in Zelda dungeons, like the Mermaid’s Cave in Oracle of Ages: where the past version affects the present. Sadly, though, those puzzles in Prime 2 don’t really come to much. Take this bit down in the basement of Torvus Bog.

You need to move a laser beam in Dark Aether, so it activates a mechanism over in the Light Aether equivalent of the same room. I assumed the puzzle would be about having to remember the layout of the Light room, and then moving the laser blind in Dark Aether. Then hopping back to Light Aether, and hoping that I put the laser in the correct location. But nope. You just hit the button in Dark Aether and it moves the beam into the right place, automatically.

That’s all there is to it. You just press a button, basically. Or, how about this puzzle upstairs in Torvus Bog. So this gate is locked in both the Light World and the Dark World, and the only way to open it is in the Light World. So perhaps there’s a puzzle where you have to open it in the Light World, and then, like, remember it’s location, and navigate back to this room in the Dark World and, oh, nope. You just drop down here and there’s a portal to the Dark World right here.

And after that, the idea is pretty much dropped: there are no real puzzles in Sanctuary Fortress where the Dark World affects the Light World, or vice versa. And so what could be a collection of interesting puzzles that arise from having access to a mirror version of the world, just becomes a slightly annoying maze of portals between two largely disconnected areas. That’s a shame. So, in the last episode of Boss Keys, about Prime 1, I talked about the Chozo Artefact hunt.

Essentially, the game stopped just before the end, and asked you to go on one final victory lap of the world to collect a bunch of Artefacts to unlock the door to the big final boss. Unfortunately, it kinda killed the pace, and by having most of the Artefacts only accessible at the very end of the game, it stopped you from naturally picking up Artefacts as you explored. Metroid Prime 2 does the same thing, again. So after finishing Agon Wastes, Torvus Bog, and Sanctuary Fortress, you return to the Great Temple… only to be told that you can’t fight the final boss unless you find 9 Sky Temple Keys, which are scattered across the entirety of Dark Aether.

There’s three in the Sky Temple grounds, two in Dark Agon Wastes, two in Dark Torvus Bog, and two in the Ing Hive, which is the dark version of Sanctuary Fortress. As before, this is a bit of a pace killer. At this point you feel ready to take on the final boss and finish the game and yet, the game’s asking you to faff around for a good few more hours. All that drive and forward propulsion stops dead as you’re asked to look for keys across the entire map.

You do get some help, of course. Certain dead bodies in the world are referred to as keybearers and when you scan them in, you get a clue as to where their key is. And, I’ll admit, it is quite fun to translate that to a place name on the map, head over there, and find the key. But what’s annoying is how the game makes you wait until the end of the game to do this key hunt. Because, first, you need the Dark Visor just to see these gross jellyfish critters who are holding the keys.

So even though you can get to, say, the Defiled Shrine, which holds one of the keys, as soon as you have the Super Missile, it will just look like a completely empty and pointless room until you come back much later with the Dark Visor. That doesn’t reward exploration, does it? So that means you need to have picked up about 13 power-ups before you can even start hunting for the keys. And from there, while you can get three of them immediately, and another after getting the Power Bomb - the remaining five keys all require the very last item in the game: the Light Suit.

So while careful exploration will net you a few keys ahead of time, most are simply impossible to collect until the very end, forcing that last minute victory lap. Why not just let people collect those keys across the entirety of the game? At the very least, you do unlock fast travel between the three zones, and the hub world, to help with this final key hunt. Okay, some stray thoughts: As always, the world of Prime 2 is littered with optional goodies to pick up like energy tanks, missile upgrades, beam ammo upgrades, power bomb slots, and secret charge beams.

These reward exploration, returning to old areas with new power ups, and general poking around. And most of them are behind interesting little puzzles, or platforming sections, or feats of strength. Very rarely do you just open a door and find an energy tank inside: the game makes you work for them, and that’s cool. The game does have some annoying bits of backtracking. After beating each main boss, you need to power up the energy reactor in the Dark World, walk all the way to the Light World and do the same thing, and then walk all the way to the main temple to get your next mission.

The one thing Retro forgot to borrow from Zelda is the fact that you can instantly teleport out of the dungeon after defeating the boss. So, Like Metroid Prime, there’s a lot to love about Prime 2. The atmosphere is top notch, jumping into the dark world genuinely makes you feel tense, and splitting the world into pieces makes the game easier to digest. And, to be honest, most of the issues with the game are small. The ammo system, some annoying bosses, those two pattern-busting items, the late game key hunt, and the missed potential of the dark world.

Because overall, Prime 2 is really fun, and I think it deserves more love than it gets. And it shows a really interesting route that Metroidvanias could take: somewhere in-between Metroid and Zelda: with smaller areas that allow for more focused exploration, and more complex puzzle solving. So Next time on Boss Keys, we’ll see where the developers took it in the next Prime game… Metroid Prime Pinball. Uh sorry, Metroid Prime 3: Corruption.