The Classic Mega Man Series was popular enough to warrant its own spin-off series, Mega Man X. That, in turn, proved strong enough for a spin-off series of its own, and in 2002 it arrived in the form of Mega Man Zero

The Zero series spans four titles — all released exclusively for the Game Boy Advance — and it was able to maintain a fairly high quality all the way through. Much of this is due to the fresh perspective brought by Inti Creates, which was contracted by Capcom to handle the series. In fact, it did such a stellar job that it was brought back for both the next spin-off series, Mega Man ZX, and classic series throwbacks Mega Man 9 and Mega Man 10.

This first game does a great job of setting the groundwork for its three sequels, but it's also a bit rough around the edges. Before we get into that, however, it's worth discussing the plot, which is surprisingly dark for a Mega Man game.

Picking up after Mega Man X5 left off (it's a long story...), this new series begins with a human female awakening Zero from hibernation. She is a resistance fighter, doing her best to aid the troops in their struggle against the evil forces of Neo Arcadia. Neo Arcadia is a utopian civilisation — or at least it is for humans. That utopia comes at the expense of robots (or "Reploids") who are being exterminated en masse in order to free up resources for the humans.

The female — Ceil — who awakens Zero knows he is their only hope against the tyranny. After all, Zero knows Neo Arcadia's brutal dictator quite well: it's his old partner Mega Man X. Yes, it's your job to hunt down and destroy the protagonist of the previous series, and if that doesn't get your attention nothing will. All four titles in the Zero series are narrative-heavy, so to say much more would spoil a lot of the fun. Suffice it to say, Zero has a long and twisting road ahead of him.

The game plays a lot like the Mega Man X titles. The physics are similar, and Zero's dash and wall jump will be very familiar to anyone who played the X series. But that's about where the similarities end. In both the classic and X series, for instance, you'd choose a level and fight through it in search of its boss. Upon defeating that boss you'd obtain a new weapon and / or ability that would help you in the rest of your journey.

Here, things are much different. Instead of selecting a level, you choose from a list of missions Ceil offers you. Each "level" is actually just a section of the game's huge main area, and you can explore them at will. For instance, Ceil may send you on a trip to defend a factory from attack, but when you're done you can stroll right back to that factory whenever you like. You might also go exploring in the middle of a mission and find yourself in the area that you liberated during the last one! It's an interesting approach, and it's nice to double back and see what's changed as a result of your efforts.

Weapons are not obtained in the traditional sense, either. Zero begins the game with a wimpy Buster, but as he progresses through the story he can earn three more items to use: his famous Z-Sabre, the Triple Rod and the Shield Boomerang. None of these are obtained by defeating bosses, however, and are all story-driven.

This is a big shake-up for a Mega Man series, as the weakness chain doesn't quite exist. Instead, some bosses have elemental alignments (either Electricity, Fire or Ice, while others are neutral) and you can obtain their elemental chips by defeating them, which you can then plug into any weapons you do have in order to benefit from their effects. This doesn't alter the way you use the weapons, but it does change how much damage enemies and bosses take from them. It sounds confusing, but in practice it's actually quite simple and an interesting attempt to evolve a very old concept.

That's not the only difference in terms of weapons, though; the more you use them, the more they level up. This means that the weapons you use most will acquire additional abilities more quickly, and while that might sound like a nice touch in reality it leads to an unfortunate aspect of Mega Man Zero: grinding.

While past games encouraged grinding for health or ammunition, Mega Man Zero has you grinding to level your weapons up — which can take a very long time if you'd like to unlock each of their abilities — and to accumulate energy crystals, which are necessary to feed Cyber Elves.

Yes, Cyber Elves. In the classic series or Mega Man X you might find some utilities or subtanks lying around the stages. Here, however, you find Cyber Elves. These little creatures come with cutesy names, but you never know what you picked up at any given time. This is a problem because it makes it difficult to remember where you found the Cyber Elf that granted you a double health bar, or became a subtank, which would sure be nice information to have the next time you play.

You can equip a maximum of three Cyber Elves at a time, and these can do anything from heal you slightly to covering death spikes to ripping half the HP out of a level's boss. Once you use them, though, they're gone forever, so you'll want to manage them as best you can, as there are a finite number in the game. Use up all the health refill Elves, and that's it — you'll never find another.

The more helpful Cyber Elves sometimes need to be fed thousands upon thousands of collectable energy crystals before you can use them. Considering how rarely and in what small quantities the energy crystals drop, you can be sure you'll be grinding for a long time if you want help from these peculiar little assistants.

And believe us, you'll want all the help you can get. Mega Man Zero is absolutely punishing. If you think you had trouble with any Mega Man game before, you haven't seen anything yet.

The levels are full of death spikes and bottomless pits, and enemies are positioned to always be as in the way as possible. Your tiny health bar doesn't help much — seriously, find those Cyber Elves — and the penalty for a mistake is very often a lost life, with 1-ups being extremely rare finds. What's more, you're graded at the end of each mission, and if you took any damage, used any Cyber Elves or took too long, your grade drops. While this absolutely gives perfectionists something to shoot for, casual players are not likely to ever see a respectable rank.

That's the main problem with Mega Man Zero: its difficulty is a bit too severe. Later games took varying steps to address this without softening the challenge, which is nice, because in this first outing it just feels like a punishment. Challenge is a great thing, but not at the expense of fairness, and Mega Man Zero doesn't master that balance.

Additionally, while we like the idea of shaking up the way you accumulate weapons, the entire game can be cleared with just the Buster and the Z-Sabre. These are both the most fun to use and the most useful overall, meaning the Triple Rod — which feels like a slower, less versatile Sabre — and the Shield Boomerang — which blocks projectiles but is difficult to use in combat situations — will barely get touched.

The fact that clearing missions leaves those areas changed can also be a problem, as it's easy to render Cyber Elves inaccessible without realising it. This means that you need to take your time combing every square inch of every area during a mission, because once you return they could be gone forever. Later games would be more forgiving and allow fuller exploration after the fact, so it's a shame pick ups get locked away so easily here.

These are issues, no doubt, but it's also worth highlighting that a lot of these problems with resources and crippling difficulty can be managed, to a degree, with liberal use of the Wii U Virtual Console's restore point feature. A key strength that really influences the experience, meanwhile, is that Mega Man Zero sets up a very interesting world, layering its narrative details nicely. For instance, your hub of operations is a decrepit and empty Resistance Base. As you rescue and assist the troops, however, you get to watch it grow and populate, which is a great thematic illustration of just how much you're assisting the cause.

Additionally, there's a lot of great character building. Ciel in particular is a conflicted idealist, plagued by guilt over something she's done in the past, and the feelings she develops for Zero over the course of the series begin here, in some nicely constructed dialogues that find her both relying on Zero to do the dirty work and fretting over his safe return. We also meet the four Guardians, who will be an important part of the next few games as well, and through them we learn that bosses in Mega Man games don't always have to be disposable. Splash Woman fans should also really enjoy spending time with her spiritual ancestor, Leviathan.

It's absolutely worth a play, as long as you're prepared to scream a few curse words and have all of your breakable possessions stored safely away. It's a fun experience overall, and extremely satisfying once you master it, with some very atmospheric visuals and a fantastic soundtrack -- these suit the GamePad screen and a set of headphones rather nicely. Zero's still getting the hang of things here, but even his faltering first steps are worth experiencing.

Conclusion

Mega Man Zero kicks off a short series that will challenge you endlessly, but is very rewarding to master. Its brutal difficulty is bound to turn off a lot of gamers, but those who stick with it — or hammer the restore point feature — will find the richest world in any Mega Man series, populated with interesting characters and pulsing with a predictably brilliant soundtrack. Its sword-heavy combat and Cyber Elf approach to upgrades aren't going to resonate with everybody — and the grinding is a genuine obstacle to enjoyment — but if you have even a passing interest in the game, it's worth seeking out. Just don't expect to be very good at it for a long time.