Mega Man Zero is a video game created by Capcom and Inti Creates for the Game Boy Advance in 2002. It's the first installment in the Mega Man Zero series, taking place a hundred years after the Mega Man X series.
Neo Arcadia, the last hospitable city on the planet, enacts a policy that demotes its Reploids into second-class citizens. This is naturally met with resistance from the Reploids, but they were branded Maverick and persecuted as a result. One cell of resistance fighters, led by human sympathizer Ciel, decide to seek out the legendary Maverick Hunter Zero. Found deep inside a derelict laboratory, Ciel wakes Zero up (having no memories of his past adventures) and joins the Resistance's cause, even if it means going up against his old comrade X, the ruler of Neo Arcadia.
The game is a platformer like the previous Mega Man games but introduces several new concepts, such as Cyber-elves, one-time helpers who can increase Zero's abilities and a rank system depending on how well Zero is performing.
This game provides examples of:
- Armies Are Evil: Zig-zagged with the Neo Arcadian Armed Forces. On one hand, they're committing ruthless genocide against Reploids, complete with "retirement facilities". However, it's revealed over time that their leaders are only doing so because they've been ordered to by X, and also because they believe that the Resistance are terrorists intent on causing mayhem to the humans living in Neo Arcadia.
- Big Bad: X at first seems to be the one pulling the strings on Neo Arcadia. Then, towards the finale, it's revealed that the X in charge of Neo Arcadia is in fact, a copy, and that the real X is the mysterious Cyber Elf helping Zero and Ciel.
- Downer Beginning: The game begins with numerous Resistance members getting killed by Neo Arcadian soldiers and Golems effortlessly.
- Early Installment Weirdness: As the first installment in the series, it has a number of quirks and features that either don't show up in future installments, or function very differently compared to subsequent games.
- The plot is very barebones, with not many cutscenes, relatively minimal dialogue, and the only substantial twist being the reveal that the X in charge of Neo Arcadia is a copy created by Ciel. While this isn't really odd by the standards of the larger Mega Man franchise, from the second game onwards the series would carve its niche by starting to focus more on story, characterization and presentation.
- The overworld is interconnected; while not exactly what you could a Metroidvania, you can physically walk to most of the areas where the missions take place, including to get cyber-elves you may have missed the first time around. Subsequent games in the series would revert to a more standard Mega Man structure where all the stages are segmented and picked from a menu. The interconnected world concept would be revisited in Mega Man ZX however, which fleshed out this idea even further.
- The game is very stingy with lives, and if you run out of lives you have to either give up a mission and have it be unavailable for the rest of the game, or reload your save and try again. Subsequent installments would make lives more common and make it so that running out of lives would just send you back to retry from the beginning of the stage.
- The weapon proficiency system, where you can level up your weapons by hitting enemies, including leveling up separate aspects to get specific moves like the aerial and grounded spinning slash, would be streamlined in Zero 2 and removed entirely from the rest of the series after.
- Elite Four: The Four Guardians, Reploids made in X's image who all act as the leaders of Neo Arcadia's Armed Forces and X's Co-Dragons.
- Fake Difficulty: For an already Nintendo Hard series, the first game is overly brutal about it for multiple reasons:
- First, you have very limited lives. As in, there's a small handful scattered across the entire game world and they can only be grabbed once. Losing all your lives means loading a save or failing that mission for the rest of the game if possible, losing any potential Cyber-Elves or an Elemental Chip it may have held.
- Second, this game and the second try for Gameplay and Story Integration by having Zero start off with simple buster shots and singular saber slashes thanks to his Laser-Guided Amnesia. The problem is a barebones Zero with no proper combos or charge abilities is so gimped that he borders on Scratch Damage towards any tougher foes, and the Guide Dang It! below makes mastering your weapons more of a hassle than it needs to be, making the game arbitrarily harder unless you spend time grinding.
- Third and finally, this game lacks the refinement of the sequels in balance and level design, so there's a multitude of blind jumps over spikes and pits, enemies ambushing you from off-screen with less than a second to react to them, and certain things and attacks that do a lot of damage to Zero than should be reasonable. This is especially bad with the Protect the Factory and Giant Mechaniloid missions, as easy deaths are everywhere combined with a Timed Mission pressure that tries to get you to make mistakes.
- Final Solution: Neo Arcadia subjects numerous Reploids to death, complete with facilities engineered for mass killing.
- Giant Mook: The Golem, mass-produced mechaniloids deployed by Neo Arcadia to serve as security forces. One of them serves as the first boss of the game.
- Guide Dang It!: While the game gives you the basics on how to level up your weapons, it doesn't at all mention certain hidden mechanics to the leveling system. While each killed enemy gives a weapon experience points, what the game never tells you, or at least only vaguely hints at, is that there are separate experience bars for different attacks with the same weapon (i.e. the Z Saber gets different experience with the normal slash, the dashing slash, the jump slash, and the charged slash). For example, while typical leveling with the Z Saber follows getting the double slash, then triple slash, the charged slash, the faster charging charged slash, and then the aerial spin and/or rolling slash, investing into killing enemies with the jump slash or dashing slash over normal slashing can unlock the aerial spin slash and the rolling slash before ever getting the double slash. The Z Buster follows a similar pattern in that it's possible to unlock the second level of the Charged Attack before unlocking the four bullets upgrade simply by prioritizing killing enemies with the Charge Shot over regular shots.
- Hub Level: The Resistance Base compared to the versions in the later games. If there's a virtual map of the game world, the base can be found in the proverbial center, and most mission areas can be accessed just by walking through the base.
- Hub Under Attack: During the game, the Resistance Base gets attacked by Neo-Arcadia, and Zero has to help in fighting them off.
- La Résistance: The Resistance, of course. They're mainly composed of Reploids who have fled Neo Arcadia to escape persecution and certain death.
- Rebel Leader: Ciel, a human scientist who is also the leader of the mainly Reploid Resistance.
- Red Shirt Army: The Resistance, who are often on the business end of the much stronger Neo Arcadian Army.
- Seemingly Hopeless Boss Fight: For the very first boss, your only weapon is the buster, which at this point can only do one point of damage at a time, and the boss's Mercy Invincibility makes it practically an exercise in futility. However, midway into the fight, X as a Cyber-elf will appear and grant Zero his Z-Saber, which will One-Hit Kill the boss. Notably, the fight is not technically hopeless before you gain the Saber—it's just an agonizing slog, and nothing is stopping someone from killing it with the buster if they're really that dedicated.
- Sequence Breaking: Leviathan will talk about your fights with Harpuia and Fefnir, whether or not you've even met them.
- Surprisingly Realistic Outcome: As the Complete Works books would go on to detail, Ciel was only six years old at the time of being tasked with making Copy-X, which she managed far more faithfully than Dr. Cain's own attempts prior — but she didn't couldn't recreate his morality for one reason or another, likely in due part to being a child working with data at best and the hundred-plus years of morality core testing Dr. Light accidentally left X in for (which was supposed to be thirty years), something Neo Arcadia had no spare time to afford in their rush for replacing their ruler. The result was a murderous tyrant in charge of Neo Arcadia that couldn't even begin to comprehend why what he was doing was "evil" and monstrous, by all means a child made to rule with force.
- Wake-Up Call Boss: Aztec Falcon, the first real boss, is known for shocking the players who have been used to the previous Mega Man games. Not only do you have a severely limited moveset by the time you fight him (unless you've been grinding, you're probably going to fight Aztec Falcon without the ability to fully charge your buster or do a three-hit combo with the saber), but the boss is also timed: fail to defeat him fast enough and the resistance members will be crushed in the trash compactor.
- Wham Line: Perhaps not that shocking, but there's this exchange, leading right into the final segment of the game:Cyber-Elf X: "NOW GO. TERMINATE THAT COPY OF ME...TERMINATE WITH EXTREME PREJUDICE..."