Accidental Aesop: BN4 of all games has the moral of "accept responsibility for your shortcomings instead of blaming them on others" thrown all over the place in filler tournament battles. Despite this, it's never paid attention to outside of Lan being upset over operators blaming their Navis.
Where Anetta's Well-Intentioned Extremist eco-enthusiasm ends and where Wily's (and PlantMan's) brainwashing begins is... unclear. Also, is PlantMan loyal first to Anetta or to Wily? In Battle Chip Challenge, he remains with her after Anetta has abandoned the WWW.
Is Raika a jerk who only cares about orders, or a soldier who honestly cares about his companions?
Is Chaud an elitist jerk who is ruthless in his orders? Or is he just putting up the act to appear tough in front of his father?
The Life Virus at the end of the first game. Despite getting hyped at as Wily's ultimate weapon, it proves a pushover (first game bosses are the easiest in the series), with a predictable set of attacks and its health is low enough that it's possible to kill it in a single turn, even with the temporarily beefed-up MegaBuster.
FreezeMan, showing up at the end of a very long chapter with plenty of backtracking, is easily undone by his stage gimmick — he's a stationary Aqua Navi standing on ice panels, subjecting him to Quad Damage from electric attacks that makes short work of him.
In Network Transmission when the Professor reveals himself after Zero's defeat, the whole Cyberworld MegaMan, ProtoMan and Zero are standing in inexplicably starts shaking. This shaking is never mentioned again.
Battle Network 4 is filled with these. Although you could blame how the scenario system works as to why nobody ever seems to comment on most of the stuff, it doesn't change the fact that there was some seriously weird stuff going on. Explanation This is because, to save on programming, characters ignore events unless they are directly affected (i.e. it occurs in their immediate location).
If you look at the series as the continuous story it is supposed to be, the entirety of Battle Network 4 is a massive BLAM. The game ends with a meteor about to destroy the planet, and it's resolved by everyone on the planet cheering for Lan and MegaMan. In BN5, none of this is ever mentioned, although Team Colonel offers a small nod to its predecessor, with the trophies from the three tournaments that took place are on top of Lan's bookshelves.
FreezeMan from the same game. The fact that he's an Aqua Navi standing on ice panels causes him to take quadruple damage from any electric attacks, so two ToadMan or ThunderMan chips should be enough to take him down. What's more, since electric attacks causes enemies to be paralyzed rather than flinch, you can immediately hit him again.
Broken Aesop: While the game assumes you don't (and for good reason), using dark chips in the fourth game essentially invalidates its message in the finale. Sure, Megaman can't use dark chips against Duo and beat his dark side, but he still has the evil portrait, can't use light chips or Doublesoul, and can still use dark-aligned chips like Static.
The fanbase is decidedly split between those who think the second and third games are crown jewels, and those who think of the sixth game as such. 3 is beloved due to its storytelling and having the most extensive gameplay in the series, but also criticized for its massive amounts of hidden information that can only be found in out-of-print materials. 6 is well-regarded for removing 4 and 5's Scrappy Mechanics and improved some other features (compare Cross System to Double Soul for example) but some of the enemy bosses are regarded as uninteresting and the English version gets a lot of detractors for removing every single piece of Boktai content as well as the chips related to the Cybeasts.note The former is somewhat understandable due to memory issues involving the cartridges, but the latter went completely unexplained.
Then there's the infamous debate about whether version-exclusive contents are totally fair or blatantly favors one game but not the other, the most notable example being the Souls and Crosses in the second half of the series. Though this gets less flak nowadays with some wanting to mess around with their preferred options in battle.
The inclusion of EX viruses in 4 and 5. Some fans might enjoy the extra challenge, others are annoyed by how they end up in an "extra effort same wage" situation. (EX viruses have higher hitpoints and damage output from their vanilla counterparts but give out the same chip, only in a different code) V2 and V3 viruses (and their chips) are off-limits until post-game, which makes the players somewhat underpowered, especially in 4. Their palettes are kind of ugly too.
The graphics overhaul for the second half of the series divided the fans over which art style is better. Although this is mainly caused by BN4's overall poor reception and the graphics actually slightly improved in 5 and 6.
Character Tiers: Or, well, transformation tiers. There have been a few agreements regarding the general usefulness of certain power-ups.
Back in the days of Style Change, the Guts style suffered because, while it buffed the Buster, it didn't provide it with enough to justify using it much when you're at the point you rely on Battle Chips more. Custom was pretty unanimously the best, outside of Hub Style in the second game.
Aqua Soul was also rather unpopular because of its lack of special abilities; mostly it just made Water chips more powerful, and its Charge Shot was uninteresting and very weak.
Complete Monster: The proudly and blatantly villainous Dr. Regal, the Big Bad of the fourth and fifth games, is the head of the Netcrime syndicate Nebula, and gleefully strives to prove his belief that humanity as a whole is evil. As Nebula's head, Regal oversees the development of Dark Chips: battle chips that grant the Navis who use them great power at the expense of twisting their minds and converting them into mindless servants of evil. In the fourth game, he deliberately attracts the attention of the alien super program Duo with the evil of his dark chips, and puts the planet in danger of destruction so he can play the hero and destroy Duo's incoming comet himself while sabotaging other, more reliable attempts at destroying it. When his deception is revealed, he tries to drop Lan Hikari to his death and attempts suicide to escape justice for his crimes. Surviving that, Regal returns in the fifth game and kidnaps Lan's father Yuichiro, who he brutally tortures in order to force him to give up the program known as Soul Net. Using Soul Net, Regal attempts to link the souls of Net Navis and humans alike to the powerful Nebula Grey program, with his endgame being to cause civilization to descend into hellish, violent, hate and rage-fueled anarchy. Vile and rotten to the core, Regal disgusts even his own terrorist father Lord Wily, who forcibly brainwashes him into becoming a better person due to the horrors he planned to inflict on humanity.
Contested Sequel: The fifth game is the most polarizing. While it fixed most of the problems with its predecessor, such as boosting the Dark Chips' viability and not making multiple playthroughs mandatory, it introduced many others, like aggravating Liberation Missions or the inability to use the same Program Advance more than once per battle, rendering competitive folder building much more challenging than before. In the end, fans often debate whether it's a major step up from the fourth game and a worthy entry in the franchise or one of the weaker games in the series.
Crack Pairing: Serenade and Slur. Genderdebates aside, these two are often paired together despite never met at all (Serenade in the manga and BN3, Slur in the anime). Although this is probably because both of them are elite-tier and feminine Navis so they are often shipped together like rivals. Some fans even slipped Bass into the pairing and make those two fighting for his affection as well, even though Bass was the one who killed Slur.
Poor, poor Mayl is the target of the Het Is Ew part of the fandom usually called the "Pink Fiend" by the yaoi shippers. In fact, even on the hetero pairings she gets some heat for hogging and having a monopoly on Lan (some say at least the Yaoi has variety), partly because of the lack of female characters around his age in the games. This results in Lan being paired with other girls who he barely had any serious contact with in the series by people who are tired of the Lan/Mayl pairing. Some other alternatives are Sal/Lan, Jasmine/Lan, Princess Pride/Lan, and even some Anetta/Lan. The latter three call upon the anime mythos, since that's where Jasmine, Mayl and their respective Navis are love rivals, where Pride/Lan pairing originates and also where Anetta isn't crazy.
The reverse also applies with Jasmine around Mayl/Lan shippers.
As a rule don't mention Chaud/Mayl around the above pairing.
For the yaoi side, Chaud/Lan vs Raika/Lan vs Chaud/Raika, and lets not forget about the Navi/Operator pairings (Lan/Bass, Lan/Protoman). This get even more complex with the dark Navis, for example, Dark Megaman/Lan or Megaman/Lan.
There's a very good reason Mr. Match has been in five out of six games. HeatMan also makes an appreciated return in Battle Network 6.
Princess Pride (in no small part to her Adaptational Heroism self from NT Warrior). Her personality change in the fifth game helps too.
Even Better Sequel: The second game was already very popular, and the third surpassed it in writing and further smoothed out some flaws in the second game's mechanics while introducing new ones in the process. This is why it's regarded as one of, if not the best, of the Battle Network games.
Evil Is Cool: Bass.EXE, through and through. That cloak he wears is just the icing on the cake.
There are several individual canons in three sets of media for the series: the games, the anime, and at least two manga series (though only one was published in America). Some fans mix details from all three, such as Mega Man being Lan's brother in the anime or manga timelines when neither adaptation officially adopts that plot point.
The infamous link between Lan and MegaMan. In canon the details are quite vague, outside "if one dies, they both die". In some fan works it can work as anything from telepathic communication to feeling each other's senses to even merging their bodies.
In some fan works using the Japanese names, there is the issue of attaching honorifics to an operator's name. Some people treat it as a personal pet name, such as Rockman calling Netto Netto-kun and getting jealous if any other navi used "-kun" when referring to him. Honorifics are simply a form of respect in Japanese and are used when talking to other people.
Fan-Preferred Couple: Tying into Fanon above, NT Warrior informs a lot of Battle Network shipping (like, say, Chaud/Yai). But since that's NT Warrior material, the details are on that YMMV page.
Some people cut off the entire second half of the series in their minds, though most people only behave as though the fourth game never happened (the fifth game certainly behaves as though Red Sun never happened, as Lan and Raika treat each other as new faces).
Battle Network 4 suffers extensively from this these days compared to the much better praised follow up to it years later due to it's Random Events Plot, the very obvious grammar errorsnote e.g., MegaMan saying "Leg's go, Lan!"., the heavy difficulty spike, and the most controversial act of all, forcing players to replay everything after you beat it the first time. This also applies to Red Sun as well, with Raika punching Lan when they first met for those who are baffled with how Raika and SearchMan ended up as one of the main characters of the anime and be buddies with the rest of the cast.
There are plenty of MegaMan-becomes-human-again stories where once he comes alive, Lan is completely forgotten and replaced with Hub.
True love stories where Mega Man and Roll try to set up Lan and Mayl together.
On the other side there are plenty of Mayl/Chaud stories where Mayl is tired of waiting for Lan to notice her and all she wants is a relationship. This also usually happens with crossover characters as well.
Betrayal fics where the government decides Lan and MegaMan are too powerful and try to separate them, imprison them, or delete MegaMan. That this was the basis of an arc in the MegaMan NT Warrior manga helps.
There are plenty of alternatives where MegaMan tells Lan that he is his brother.
AU stories where Hub is still alive.
Or if Lan died and Hub was still alive.
There are a few divorce stories that feature Lan's parents splitting up and Lan trying to cope with it.
Some stories will have KnightMan a girl underneath the armor for Lan/Pride fics. (WoodMan has been declared female in at least one fanfic, though not tied in to any Lan x Sal shipping).
Bass and Serenade shipping fics aren't unheard of, most of which treat Serenade as a female.
Serenade is supposed to be a perfect being, incorporating aspects of both genders (hence the androgynous appearance), and has attacks named like "Saint's Light".
Bass, by comparison, is darkness-based like you wouldn't believe. Wants to kill humanity, wields Dark Power from the instant of his discovery, etc.
Franchise Original Sin: A lot of the problems BN4 has are evident in Battle Chip Challenge. There's lots of padding with needless tournaments with occasional references to the A plot, questionable writingnote an adult opponent you face in the tournament refers to himself as an elementary schooler, meaning either the dialogue got placed in the wrong spot or he really shouldn't be in charge of a program like a Navi and bad characterization, emphasis on unlocks and repeated playthroughs, among other things. The difference is that while BN4 was made by Capcom, BCC was made by Inti Creates and was very obviously a spinoff. As such, despite being plenty worse, it never really did much damage, let alone end up killing the franchise.
"Funny Aneurysm" Moment: In the early 2000s, the idea of cyber crime wreaking havoc on a global scale seemed pretty far fetched. Then came wave after wave of hackers breaking into company databases to steal money, identity information, and expose top-secret and scandalous information and suddenly Battle Network's antagonists don't seem as unbelievable as before.
Goddamned Bats: Viruses in the later areas of the game (especially the more maze-like ones) will constantly distract you from any task you happen to currently engaged in (e.g. running from the monsters in Netopia Castle network) and will take up far more of your time than they deserve to. The viruses in the later portions of the Undernet and any post-game Bonus Dungeon are so nasty they ascend right to Demonic Spiders.
Hard Heads are almost constantly shielded viruses that un-shield only temporarily to launch a cannonball that will punch a hole in your field. At higher levels, they can box you in if you aren't careful.
Mole viruses in the third game have low HP, but they are immune to everything except from ground-affecting attacks. When they emerge to attack, they always appear behind you, giving you a short window to circle around and attack them.
The Lark series of viruses - those that drop the Wide Shot chips - fire shots that cover a wide area in battle. Mercifully, they never attack when they're in the middle row, else their attack is undodgeable. Not so mercifully, the wide coverage of these attacks make them notorious for breaking in-battle Mystery Data, sometimes within the very first second of the fight.
Moloko series viruses in the 4th game. They're sheep with a rather basic ability to charge at you. What makes them irritating is that their wool will protect them from any damage (enough damage will shear it off and make them vulnerable) meaning that you have to hit them with buster shots or weaker attacks first. You then need to hit them quickly when they're vulnerable because their wool will regenerate once they move offscreen and Wrap Around. Later versions are even worse, needing more hits to shear their wool.
Appley viruses in the 5th game pretty much serve to ruin a player's attempt at S-ranks or 1-turn Liberations. Most of the time they reside in their shell, only being vulnerable when emerging to attack. The shell makes them immune to everything but Fire attacks. Not even Breaking attacks work on them. Also, if somehow they are killed first, they heal the other viruses.
In the 5th game, the predictable CanoDumb enemies are replaced with CanGuards, which are similar except they have a shield that blocks non-breaking attacks when not attacking. While their first versions can't use it, their later versions do, which means you have to force them into sending out their crosshair or into attacking if you want to hurt them.
Kettle Viruses in the 6th game. They lack proper HP and have a temperature count that increases when they are hurt, and once it reaches 100 degrees they explode. Notably, their temperature will quickly drop if you aren't attacking them, and later variants gain less temperature when attacked, making them a pain to kill.
Goddamned Boss: We had too many examples, so they got moved to the trope page. In summary:
Most of the bosses from Battle Network 2 have gimmicky and obnoxious attack patterns that are less interested in being challenging and more interested in being completely unfair, usually through some combination of Spam Attack, Super Speed and being only vulnerable when they're about to attack* which they rarely do, making it frustrating if you want to obtain their V2/V3 chips by beating them under a strict time limit.
BN4's ShadeMan, who no-sells anything other than GunDelSol if attacked in his Navi form. If hit, he splits into a swarm of bats and retreats off-screen, giving players only a few seconds to guess which bat is the real ShadeMan in order to inflict damage. And don't bother trying to end the battle with that Mystery Data intact on the field, just grab that Giga Chip from Laserman instead, as the bats WILL destroy it eventually.
The first game has the Cutscene Pause glitch, which would allow you to skip cutscenes by exploiting the brief window in which you can bring up the pause menu; this can actually be used to skip the final boss of the game.
"Gospel Duping" is the name of a Battle Network 2 exploit that allows players to collect more copies of chips than the game intended. Beating Gospel will reset the game to your last save point, with your chip folder and completion markers intact, but it won't account for any changes to Mystery Data or the like, allowing you to collect from them again.
The ProtoMan tournament fight at Blue Moon has absolutely terrible AI, which insists on doing nothing but occasionally using Fighter Sword, and only from the center-right column. Stealing that column with a basic Area Grab makes him entirely helpless.
In Battle Network 4, if a dark Megaman loses all his HP on the same frame a poison panel depletes it, his HP is completely removed and all further damage does nothing to him, passive or direct. Damage is still registered if it's an attack, but it simply doesn't do anything.
In the original Japanese version of Team of Blues, if you decline when Meddy asks you if you want to do a Team Liberation, and then use a Net Navi on a panel at some point opposite her, the game will behave as if you had tried to do Team Liberation anyway.
Battle Network 3's Bug Style invokes an In-Universe version: you unlock it by deliberately glitching Mega before sending him into battle, it endows you with positive and negative bugs at the start of each fight, and as you level it up, it gives you the Bug Stop program (which ignores Navi Customizer bugs so you can have a little more freedom when you customize Mega) and the Dark License program (which allows you to use certain Giga Chips without opening a Dark Hole in the field first).
In-Universe versions of this trope can also apply to any game where the Navi Customizer is available. Depending on the nature of the bug and its severity, one can intentionally cause bugs with their Navicust programs and use them to their advantage. A famous example is the "Humor glitch", which, in the latter three games, causes Mega's Emotional state to randomly change between available states, including the damage-doubling Anger and Full Synchro. With luck, early double damage without needing any setup can lead to very quick battles.
Good Bad Translation: For some reason, the three-Spreader Program Advance in Network Transmission was translated into English as "GigaDeth", which Roahm Mythril noted just begs to be said with a heavy metal growl.
Harsher in Hindsight: Many of the cyber attacks in this series that appeared to completely outlandish at the time have become much closer to reality with the rise in cyber crime.
A scene in 3 where Mamoru nearly dies from complications during a WWW malware attack on the hospital around the time he was scheduled for an operation becomes more sinister when you realize that it is theoretically possible to break into a hospital's intranet and tamper with the vital equipment hooked into its network via their embedded systems.
Not so theoretical as of 2016. Say hello to ransomware, the nasty attack trojan that locks every device on a network and encrypts everything on their hard drives until a ransom is paid. The most common targets? Hospitals, where those devices can (and very often do) include surgical equipment and life-support machines. A hospital will rush to open bitcoin accounts and pony up thousands of dollars to end the crisis quickly and save as many patients as they can.
In 3, all BBS posts made by Undernetters are anonymous.
The Undernet in general is portrayed as a Wretched Hive. In the 00s, this became what the Dark Web was portrayed as, and in 2015, what the Deep Web and Dark Net were portrayed as albeit Nightmare Fuel heavy.
Bridging this and Harsher in Hindsight, over the course of the early 200x years, malware attacks have increased in frequency and become more high-profile. Between Flame, Stuxnet, and the spam attacks made against Spamhaus that threatened to knock out an entire major router node, it's clear that the Battle Network series is eeriely prophetic about cyber warfare.
In Battle Network 6, one of the sidequests involves finding a lawyer to deal with the quest-giver's fraud case. The lawyer NPC you talk to turns out to be a boisterous, hotheaded crusader of justice that loves to shout "JUSTICE WINS!". This game was released a year before Mega Man Powered Up introduced us to its incarnation of Fireman.
Towards the end of Kill la Kill, one character fires a barrage of Anger Impacts to destroy a barrier.
Zennies are the in-game currency and can exist both as real life cash and as data in the web, generated and free for anyone to pick up. Years after this series have ended, Bitcoins became a thing (although nowhere near as prolific).
Some Wily dialogue in the first game anticipates the Doge meme by over a decade.
Team ProtoMan gets this sometimes, especially from speedrunners, as it's perceived to be the harder version of Battle Network 5. This is because Team Colonel offers more viable teammates during Liberation Missions and the game-breaking Knight and Number Soul Unisons early on.
While not to the same extent as the above example, Cybeast Gregar is considered to be tougher to beat than its counterpart. This is partly because the earlier areas of the game are filled with Aqua-type viruses, who provide useful chips for Falzar version's Spout Cross, but are deadly to Gregar's Heat Cross. This also extends to the final bosses, as Gregar has much more HP and an erratic attack pattern, making Falzar look like a pushover in comparison.
It's the Same, So It Sucks: Go ahead. Say you're glad they're keeping the old graphics and Internet in the BN1 remake around fans. Although this is because the original Internet was very ugly looking and difficult to navigate, which may be mitigated by the map function revealed in the preview.
Memetic Loser: The Lifevirus. Not only is it by far the easiest final boss because of Megaman getting his buster upgraded to busted levels immediately before the fight, but via a glitch it's skipable.
Duo's Anger Impact has become the symbol for how much everyone hates Battle Network 4.
Also from Battle Network 4: "We have become Masters of Science." note Syntax issues and awkward delivery aside, this line just becomes hilarious when you consider the gratuitous amounts of Artistic Licenses the series pulls off, and they're not just exclusive to computing.
Thanks to various screenshot Let's Plays of the series, the fanbase has grown a habit of trying to take screencaps of various mugshots in the middle of their blink animation. If successful on a happy mugshot, the character is suddenly transformed into a Smug Smiler.
A Let's Play of MMBN1 criticized some players for not knowing what is a Program Advance (P.A.) because they didn't talk to NPCs who mention it all the time. The problem is that it's not that they didn't know about what it is, they actually didn't knowwhichBattle Chip combinations form what kind of P.A. in the first place.note There are some exceptions, but those only apply to really basic P.A.s. Making things even more confusing is that some P.A.s might get carried over to the next game but require different chips such as PoisonPharaoh, 2XHero note Pronounced "Double Hero". and MasterStyle. It's like the Harvest Moon recipes, except that you cannot do things like bribing NPCs with gifts if you want them.
For the longest time, American fans have been mad about not being able to play the additional Boktai content of Battle Network 6, and have blamed the matter on Boktai's limited popularity in the west. Not so — the actual reason is that the game's memory was so jammed full of content that material had to be removed to make room for the English script. The Boktai content, being cool but largely unimportant, therefore got the axe.
Most Annoying Sound: Every game has specific songs that play during the terrorist attacks. All of them are repetitive, 5-seconds long loops that are bound to make you mute your system. During the course of the plot they don't last very long, but when you initiate the endgame, expect to hear it throughout the entire overworld when the world is put in crisis. For some games, this theme persists throughout the postgame, only stopping when you choose to jack in.
Duo's Anger Impact move, which has him projecting a giant pink angry face as a laser beam of some sorts. It looks silly, especially in contrast to his default super-stoic expression.
This also happens with some of the scenarios. The fact that Mayl and Ms. Mari are so excited for an internet-controlled dishwasher of all things after all the hijackings of household appliances can be somewhat silly.
Ms. Madd herself from the first game seems like she was built up for this. However, her expression coupled with her actions and taunting of Lan make her surprisingly threatening. Her Navi, on the other hand, is just plain ridiculous. HC Bailly called attention to how awkward it looked when he was bouncing up and down while Roll was on her back.
Double Team DS makes the otherwise badass Colonel much more comical, thanks to his voice actor giving him a jarring Russian accent and delivering his lines in a spectacularly hammy way.
In Megaman Battle Network 3, at one point you must fight a custom Navi as a boss to advance in the ranks. This actually changes depending on your version. In White, you get MistMan who has a rather unique appearance. Blue, on the other hand features BowlMan◊, who throws bowling balls and bowling pins at you. It is simultaneously unintentionally hilarious, yet charming and awesome at the same time. Especially since they are ranked Undernet navis, and they are both decent people.
Drillman.EXE from the same game. His design and Dumb Muscle attitude is unintentionally hilarious, yet his status as That One Boss forces players to adjust their folder and their playstyle.
Older Than They Think: The map function seen in Double Team DS and Operate Shooting Star is actually introduced in the Japanese versions of 6, although it is located on a signboard in the respective areas instead being accessible to the player via the lower screen.
Padding: The Castle stage in the second game could be bad, but a lot of it can be avoidable if you just run out of the way of the zombies.
The fourth game absolutely loves sending you to the end of Park Area 3. Even with the best possible luck, you'll still need to go there multiple times for arbitrary reasons. The game is full of needless padding, and while this isn't the worst (that would go to the Protoman scenario), it's the most prominent.
Battle Chip Challenge requires you to complete all the tournament variations before proceeding to the next rank. Even characters that by all means should be seeded (Chaud and Protoman, Lan and Megaman) have to start at the very bottom. While there's a fast forward option for the completely automated battles, it still drags on and on.
The FlameMan story arc in 3. Not only did Lan fall into a Heroic BSoD after being tricked by Mr. Match to burn SciLab, almost killing his father in the process, Lan and Mega's reactions to Mr. Match giving the shady data showed that this could have been avoided at the first place, but the plot cannot progress unless you did what Match wanted you to do. And this is right after Lan is honored as a hero for saving the Beach Hospital from Anetta and PlantMan in the previous arc. This in turn nets the WWW the final Tetracode which allows them to steal Alpha and use it to wreak havoc, and a series of events that leads to one of if not the most emotional MegaMan deaths in the series.
In Battle Network 6: Falzar Version, Cybeast MegaMan goes on a rampage and Lan is forced to send a friendly Navi to stop him. Problem is, as soon as the mission is complete, said ally will be ambushed and nearly killed by Colonel, and depending on who you pick this outcome will seem even crueller: Some of your choices are SpoutMan, who is by all accounts a child; TenguMan, who feels extra pain from Sword-based attacks; or TomahawkMan, who is a former member of Team Colonel.
In the sixth game, Mick and Tab for replacing long-standing characters Dex and Higsby, respectively. Made worse by the fact that, in spite of being Lan's new friends, you never get to have a match with them, and they are given generic Navis to boot.
The Double Soul mechanic is this for those who thought Style Changes were more rewarding and adaptive to the player's preferred playstyle. The Cross Unison system in the sixth game was an attempt to rectify this, mixing characteristics from both previous mechanics, and was for the most part well-received.
In the anime, Roll has an increasingly blatant crush on Mega, who is Oblivious to Love (much like his operator). Some fans believe that MegaMan knows of Roll's crush. Some of their stories portray him as being so lovestruck that he is willing to do anything for her sometimes at the cost of Lan. She's also depicted using the evil chip from the anime on herself intentionally and shamelessly flirt with the other Navis to make MegaMan jealous for not responding to her affections. This occasionally overlaps with Roll joining a villainous group, presumably because her expyHarp Note did the same thing in Star Force 2, albeit for different reasons.
There are also plenty of fanfics that portray Mayl as desperately wanting any form of love from Lan to the point of tricking him into giving her affection or leaving him for another man; the disturbing part is that they are still 10 in some of these stories.
Many fanfics love to portray Mayl as being overtly possessive of Lan to the point of her getting upset at him even interacting with other females. This is turned Up to Eleven in yaoi-centered fics, as she is depicted as homophobic as a result of Lan being attracted to guys.
Somewhat downplayed, but many people like to portray Dr. Hikari and MegaMan as always holding secrets from Lan, usually under the context that he isn't ready. In canon, there is no indication of a lack of trust towards Lan.
CloudMan and CircusMan are as hated as BubbleMan is. They are obnoxious in bossfights and cutscenes while getting away with what they usually did due to their ridiculously strong Plot Armor. The latter gets "bonus" points for being a creepy Monster Clown.
Chisao, Dex's little brother, does little but cause problems for other people. In his very first scene in 3, he basically hijacks the subway system by preventing anyone from getting on until they find his big brother for him, and refuses to simply say who that is, insisting that his brother is the greatest net battler in town so everyone ought to know who he means. While getting kidnapped during the Zoo Incident wasn't technically his fault, it didn't really do much for him, either. In Dex's storyline from Battle Chip Challenge, he tries to convince Dex that he should replace GutsMan, and in Red Sun, he actively tries to sabotage Lan's ability to compete in a local tournament.
Some fans aren't at all fond of Mayl, Dex, Yai, and their Navis on the grounds that they rarely do anything besides send Lan or Mega on errands and get into trouble. It doesn't help that their competence regressed with each installment (save for Dex and Guts in 3) and their passiveness. (For instance, in 6, their incompetence allowed WWW to kidnap MegaMan and turn him against Lan.)
Glyde isn't particularly hated, but he has so little effect on the plot that he's actually considered to be the most worthless character in the games due to being The Unfought and not having a unique moveset, things that GutsMan and Roll do not suffer from. He has maybe one or two scenes of Cutscene Power to the Max in the first two games, teams up with GutsMan and Roll against BlizzardMan in the fifth game and helps protect Lan from WWW's mooks in the sixth game (which also reveals that his Signature Move is called "Glyde Flash"), but that's about it. You could remove him from these scenes and absolutely nothing would change.
Any point where you need a certain chip of a certain code to progress the plot, especially if it's acquired from a rare encounter virus. Battle Network 3 players will be reminded of "Iceball M". Battle Network 4 players will recall the entire ColdMan scenario.
The Press program which allows MegaMan to walk on the tiny paths. The problem is that while on the tiny paths, Mega Man moves much slower and random encounter viruses still show up, which may cause you to forget which direction you were moving in since MegaMan's smaller size makes it difficult to tell which direction he's facing. Another factor is that it's a program and not a key item, so be prepared either to open up your NaviCust and fiddle around for about thirty seconds every time you need to use the near-omnipresent tiny paths, or have to deal with wasted space in the NaviCust for a program that has no combat applications.
There was also the Energy Change program which is required during the PlantMan and FlameMan scenarios where you have to either use a fire (PlantMan) or aqua (FlameMan) element battle chip so you can burn a plant/extinguish a fire which permanently gets rid of your battle chip. PlantMan's scenario is more forgiving, as the hospital network is populated with fire viruses that grant you an alternative supply of fire chips, and you only needed to burn down just enough plants to proceed. The FlameMan scenario offers you neither consideration, demanding that you extinguish all fires across the Net without changing the random encounters to help with your aqua chip stock.
While Style Changes are not hated, the element is determined randomly, which is incredibly annoying to keep track of, considering how the main game requires you to run through multiple environments while still leveling up the same Style Change. Elec Styles, which have very little raw power, get hated the most.
Regarding Navi fights, BubbleMan and DarkMan's beta forms will only show up if MegaMan's health is low and if there is a bug in the Navicust respectively.
A minor one, but in 3, Dex moves to Netopia late game. As such, you can't jack into his computer or use his shortcut to ACDC Square for some time.
Similarly, you cannot buy Battle Chips in Aster Land during 6's endgame since Tab joins Lan and co. to the final dungeon.
Forced tutorials at the beginning of every game. Even if you know everything about the Battle Network series, each game will put you through 3 tutorials usually on things you already knew like only using chips that are the same or those that share a code.
5 introduced Liberation Missions, an Unexpected Gameplay Change that mixes standard gameplay with Turn-Based Strategy. You have to liberate Dark Panels by having the usual virus battle. If you complete it in one turn (before the Custom Gauge fills up) you're rewarded by having adjacent Dark Panels liberated as well. However, unlike regular battles, once the Custom Gauge is full, the Custom Screen shows up automatically, which couts as a turn and you only have 3 turns to win. If just one virus has so much as 1 HP, you lose and have to liberate the panel again. Also, the battle field isn't always even. You may start out with only 2 columns as opposed to the usual 3 and worse still, there are surround battles where you are in the middle 2 columns while the viruses have 2 columns to the side and excluding viruses that are stationary or can only move within the same column, they can teleport making it easier for them to dodge your attacks and with attacks coming from both sides, things will get hectic quickly. There are also traps that damages or paralyzes the navi that activated them. They look like item panels which means online maps are the only way to tell the difference between items and traps. Traps can hurt you if you accomplish a 1 turn liberation or if you use NapalmMan or TomahawkMan's command to liberate panels, they'll destroy any helpful items (except for barrier keys) but activate traps anyway.
In 5 and 6, the inability to use the same P.A. more than once in a single battle hampered folder building, forcing players to rely almost entirely on a few select multi-hitting chips in order to make a competitively viable folder.
As you could probably tell from many other entries on this page, fans did not like the fourth game. Thankfully, the fifth one is contested at worst, while the sixth is a Surprisingly Improved Sequel.
The two spin-offs that made it to the West, Network Transmission and Battle Chip Challenge, were released to lukewarm reviews. The former is criticized for its poor implementation of the Custom gauge mechanic and absurd Early Game Hell, while the latter is derided for being pretty much the ultimate example of Game Plays Itself. Their status as canon is hotly debated as well.
The Japan-only Operate Shooting Star was a critical and commercial failure. Despite being promoted as a crossover with the MegaMan Starforce series, it was instead a direct remake of BN1 with the addition of a single extra event through which Geo Stellar could be unlocked as a playable character. Many would agree that BN1 has not aged well in comparison to the other Battle Network games, and even more people concur it was a disappointing way to send off both franchises.
Surprisingly Improved Sequel: The first game was rather oddly balanced, with clear Broad Strokes showing as the programmers were still figuring things out. The second game refined the battle system and had better writing, such that it is regarded by fans as one of the best in the series, only matched by the third. The fifth game served as this to the fourth by actually having a plot. The sixth is this to the fifth, with some seeing it as on par with the second or third in quality.
Several electric attacks in the first game, most infamously thunderballs, cause a status ailment that causes MegaMan to take damage every time he moves. When that happens, the duration of the ailment resets itself, so the player either has to wait it out while staying perfectly still, which leaves them open to other attacks, or be forced to tank the damage and watch their Busting level plummet.
In the final chapters of 3, GutsMan hits his Beta form, and he demonstrates how he Took a Level in Badass by using his own Program Advance. The moment "Z-Punch" appears on-screen, he turns invincible for several seconds and throws out a series of punches which also don't trigger Mercy Invincibility. While it may be a Desperation Attack used when he's close to being defeated, be prepared to kiss your S-rank goodbye.
The final bosses of 4 and 5 have an attack that can crack or destroy most of the battlefield, leaving you with very little space to maneuver and boxing you in unless you've equipped AirShoes.
In the second trilogy, Bass' rapid fire attack changes from a series of sparkles that dash across the rows to a machinegun that randomly hits each panel of your field very, very quickly. In 6, this attack doesn't trigger Mercy Invincibility and is well able to take two thirds of your health in instants. Beating Bass becomes a matter of never allowing him to perform this move.
In 5 and 6, Colonel gains one of the most impressive-looking attacks in the entire series: once you're under a certain amount of HP he'll start throwing his cloak with no warning. If it connects, the screen goes black and a slash shreds across it, instantly deleting your character unless it is MegaMan with Undershirt on. His RV version will start performing this when you're at 550 HP. This is also notable in that it's the only attack in the series that activates depending on Mega's HP instead of the user's. If it won't (seem like it will) delete him, Colonel won't use it.
That One Boss: There's at least one per game. A more thorough list is detailed here, but here's a brief list:
ProtoMan.EXE is usually one of the most aggravating bosses to fight in most games, if only because he tends to block anything thrown at him with his shield until he comes out to attack, which he does very quickly, leaving only a small window of opportunity to strike back.
DrillMan.EXE in 3, for being nearly impossible to hit without breaking chips, which were either scarce or impractical in the first three games.
BubbleMan.EXE in 3. The continuous spew of damaging bubbles not only blocks your attacks, but also severely hampers your movement and a new one is made the instant you blow one up. Coupled with all the other obstacles thrown on the field and the fact his third version can only be encountered when Mega's at critical health...
QuickMan.EXE in 2. His attack pattern is very similar to Proto Man's above. The only saving grace is that it has limited variety in attacks and has low hitpoints, which stems from QuickMan being an early-game boss.
SkullMan in Battle Chip Challenge has a great deal of health, a powerful attack, and has a scarily well-built program deck. His power chip is the Curse Shield, which not only shields him, but has an absurd amount of HP in its own right and it will eat your attacks for breakfast (and every time you hit it, it'll take a bite out of you, too). To add some nasty icing to this awful cake, SkullMan is often found on a poison stage, which will eat through your health and chips while you struggle to land each attack, hit by individual hit.
GridMan in Battle Network 5. His support clones will regularly block your shots, charge to attack you, and make it very difficult to efficiently Area Grab him since even when inactive and dead they take up panels along his front row. GridMan himself meanwhile has a lot of HP (2000 in his strongest form), is immune to flinching, has no elemental weakness to pick on, tends to stay in the back row out of range of many attacks (again, Area Grab is tricky to get off properly), and his attacks, particularly when used alongside his clones, aren't easily dodged.
The Protectos and Numbers in the Bonus Dungeon of the second and third game respectively combine this trope with Puzzle Boss, requiring the player to destroy them in a single hit, and for the latter, even need to be destroyed in a specific order. While all this is happening, the Protectos count down to a massive explosion; the Numbers are docile until attacked out of order, at which point they retaliate with an attack strong enough to deliver a One-Hit Kill. On top of that, while they are found in fixed locations, their encounters are inescapable, and Protectos don't give any indication as to where they are.
Nebula Grey Omega, who not only has the most obscene amount of health of any boss in the series at a whopping 4000 HP, but also happens to be the final boss of the game that made P.A.s unusable more than once per battle. He hasn't changed much in comparison to his regular form, meaning he is still attacking constantly while being vulnerable only 50% of the time, but the boost in HP made him such a Damage-Sponge Boss that it demands mastery of the Chaos Unison mechanic and liberal use of chips like Invis and Bubble Wrap to be manageable, and even then it's still likely that you will run out of chips before the battle is over. To top it all off, Nebula Grey Omega also has an attack that heals him and pierces through those two defensive chips, dealing heavy damage and prolonging the fight even further.
Bass tends to be the hardest boss of every game, but his XX version in the fifth game is beyond ridiculous. He has 4000 HP, much like the True Final Boss, but also a regenerating barrier that can absorb up to 200 damage. Oh, and not only are his attacks much faster, but they can deal up to 900 damage! To top it all off, he offers zero rewards upon being defeated, so he pretty much only exists to make players dread random encounters in Nebula Area 6. The battle can be made slightly less difficult by setting North Wind as the Regular Chip and using it to permanently get rid of his barrier, but there is no real counter to his other abilities other than getting the right chips at the right time.
The Dark Soul Navis in the post-game of BN4 and BN5, who keep the annoying gimmicks of their regular counterparts (like Searchman's invisibility or ToadMan's instant lilypad teleportation), on top of being able to use any chip the player has activated throughout the game. This includes Navi chips, Giga chips and Program Advances, which means they have unlimited access to nearly unavoidable game-ending attacks, and of course they spam them like there is no tomorrow. Make sure to pack some Full Energies before attempting to take them on.
The first game's Waterworks level. You have a (somewhat) long stage full of slippery ice. It seems like you deleted what was causing the water to get held up but guess what? Now the water is purple and everyone's poisoned so you have to go through the stage all over again.
The Power Plant, also in the first game. While veterans to the series won't mind the lack of post-battle healing (the later games had it as a facet of the system as opposed to a one-time gimmick) there's the fact that you're on a limited battery life, have to solve frustratingly vague logic puzzles, the the random battle rate is through the roof and a large part of the level is an invisible maze. You can't jack out either, so it's possible to be trapped in a nigh-unwinnable situation. Oh, and did we mention that the stage ends with three-round back-to-back-boss fights, with one of them being a Hopeless Boss Fight and the other pits you against ProtoMan?
In the original game's school network, you have to input passcodes to open gates and the answers are given to you (i.e. count the number of chairs in the classroom, that number is the passcode), however, some gates don't give you any clues meaning you have to guess and if you're wrong too many times, the passcode changes. Thankfully, it does tell you whether you're too high or low and if one digit is correct, you're told which digit to change.
In 2, the Freeze Man scenario requires a lot of backtracking between Netopia and the Undernet.
In 3, the World Three guard robots have security claws that will take you to a certain checkpoint if you get caught. While the claws do have patterns, it can be difficult memorizing them and there are times when a security claw overlaps the shadow of another security claw making it easy to get yourself caught. Some are also ridiculously fast giving you only a few seconds (or less) to run past them while others are incredibly slow forcing you to wait until they pass you.
It's not particularly hard, to be honest, but you'd have to search hard to find five or more people who enjoyed the carnival levels in BN4. Brrr... that music.
MetalMan's scenario in Blue Moon. It involves Tamako forcing you to study from her master (a Navi by the way) before you can challenge her. Said master then drags you to a fetch quest for food AND drinks in the Park Area. Some might make a mistake of only bringing him the drink, since he only mentions getting him food when you talk to him the second time. Only then will he teach you the minigame portion of the scenario, which involves punching rocks with very precise timing. Depending on the rock's color, the gauge goes faster and faster every time. After that then Tamako challenges you to punch rocks under a strict time limit before you can Net Battle her in the tournament. Aside from the precision needed to break them, MetalMan can and will teleport freely to anywhere he wants, while you have to walk instead. And once he gets to the rock he wanted, you cannot break it and have to find another one nearby. Even worse, this part has 3 rounds you have to get through. At least there's a break between each round. The only saving grace of this scenario is the reward, which is one of the most broken Souls in the series.
The third quarter of BN5 makes you navigate the labyrinth that is End Area, which is harder to navigate than the Undernet, has 5 areas and two Liberation Missions compared to Undernet's 4 and one Liberation Mission. Due to this said portion of the game is spent on lots and lots of backtracking around End Area...let's say after passing that part of the game you will be sick of it.
The Samurai-Whacking minigame in NumberMan/SearchMan's scenario in the fifth game. What really makes this one infuriating is that it's mandatory in order to progress, the robots appear quickly and without following a pattern, and if even one of them touches Lan the challenge starts over. It's even worse in the DS version, where this minigame must be played over and over if the player wishes to obtain the Boktai-themed chips.
DiveMan's scenario in the sixth game. It's an Escort Mission where MegaMan must transport 3 to 4 Mr. Progs to specific tanks in the beginning of the area while avoiding sharks. Sounds simple, but only one Mr. Prog can be transported at a time, the size of the screen makes it hard to see incoming threats, and if a shark manages to swallow your escortee he is transported all the way back to his spawn point. Save Scumming will be your best friend here.
The Undernet in all games is this. While the normal Nets' layout is fairly straightforward with only a few frustrating turns, the Undernet takes almost sadistic glee in putting arrow panels in the worst of places, usually making it so that one wrong turn ends up putting you right back at the entrance (or worse, forcing you to walk back to the entrance just to try again). On top of that, the enemies become Goddamned Bats at minimum and Demonic Spiders at their worst, due to a combination of difficulty spike, weird powers you haven't seen anywhere else before, treacherous terrain, and putting them in combinations that turn otherwise straightforward battles into what could be described as "Super Meatboy on a 3x3 chess board".
Due to the design of the Net, it's entirely possible to wind up in the Undernet in 1 completely by accident. The kicker is that the Undernet has the exact same aesthetic as the rest of the Net, so unless you talked to certain NPCs who warn you of what's ahead, you're not going to know until you hit a random encounter with viruses much stronger than you can handle. On the plus side, if you're good enough to handle these encounters, you're rewarded with chips far stronger than the game expects you to have.
The Undernet in 4 is easily the toughest in the entire series, due to it sporting some very mean Demonic Spiders (see the subpage for more details) while the player's limited chip selection makes it difficult to exterminate the viruses with ease. On top of that, even accessing the Undernet needs the player to track down and purchase some key items in order to make the C-Slider to access its only entrance.note An alternative entrance does appear, but not until late in the playthrough If the player ends up with SearchMan's or ProtoMan's scenario, visiting this hellish place becomes mandatory, and the scenarios themselves don't make things any better. ProtoMan's involves a Pixel Hunt for a handful of "keys" that will allow Mega to proceed into the depths of the Undernet, which wouldn't be too bad if not for where this takes place and the poor translation giving out misleading hints. SearchMan has you scour the Undernet while occasionally dealing with quick-time events that take a large chunk of your HP if you make a mistake. All while the random encounters are still on.
Pretty much every area that only becomes available after beating the main campaign, but the third game's Secret Area and the fifth game's Nebula Area really take the cake. The former is a huge maze that cannot be jacked out of, while the latter is the stage of a series of long and obnoxious Liberation Missions that are mandatory in order to obtain upgraded weapons.
Several NPCs will offer the player a hard-to-acquire chip, but only if they have a chip of a particular code to trade for it. Sometimes the chip of that code can be easily obtained through the Order system, or is part of a Chain of Deals that eventually lead up to something worthwhile. When this isn't the case, it's usually a rare encounter in the Bonus Dungeon that requires a high busting rank to attain. Get good and lucky with virus busting, or ridiculously lucky with the Chip Trader.
100% Completion of the Chip Library can be a bit of a pain depending on the chip(s) you're missing. Usually, you can get a greater part of them by playing the game normally, and a few require some specific grinding for... And then there's the ones that flat-out require manipulating the RNG of the game through the chip folder and enemy actions to even have a remote chance of getting. Don't feel like having to grind for specific chips and performing every action flawlessly? Well, hope you like them being a Luck-Based Mission from the chip trader then! Some of the most infamous ones from the first game include Howitzer and Dropdown.
It gets even more tedious when you're trying to obtain chips to form Program Advances, which also have a completion record to them. Not only do you need a specific chip, you also need it in a specific code, which means either having to S-Rank a hard-to-kill virus or even intentionally tanking your Busting Rank at times.
Some of the chips needed for Library completion can only be obtained from Bug Frag Traders. What makes this difficult is that Bug Frags are painfully scarce most of the time. While Battle Network 3 makes it very easy to farm them with a Counter Attack on rematchable bosses, the other games are not as merciful — Bug Frags in 2 only appear in certain mystery datas, while in 4 to 6 they are obtained either from overworld green mystery data (at one Frag apiece) or from in-battle mystery datas (anywhere between 1 to 5). The latter often means defeating viruses in the Bonus Dungeon while trying to preserve a mystery data that shatters when anything so much as a Buster shot grazes it, and sometimes after all that hard work the prize isn't even what you want. You can also get them from Liberation Missions or in the Virus Battler minigame, but both methods involve performing the same actions over and over again and are just as tedious.
Anything that gives you a key item in Battle Network 4, most notably the C-Slider and Nebula Code. Both cost a non-trivial sum - 9,000 and 10,000 Zenny respectively - while involving backtracking to acquire them. Due to Battle Network 4's New Game+ structure, each time you start a new cycle, those items are not carried forward, needing you to spend more time and money just to re-open various areas of the net. The C-Slider even becomes mandatory for certain story scenarios as it is needed to access the Undernet.
They Changed It, Now It Sucks!: Pretty much nobody in the fanbase likes to refer to the samurai NetNavi, YamatoMan, by his English name, "JapanMan.EXE".
Sean, once-leader of Gospel. He only appears once again in the series after Megaman Battle Network 3, as a competitor in Battle Chip Challenge.
Mamoru, administrator of the Undernet, and Serenade as well, for that matter, never reappears after the third game.
Zero, the Battle Network incarnation of the franchise's greatest Memetic Badass. At the end of his own game, he decides to go wandering... and never reappears, not even when later games introduced counterparts to Colonel and Iris he could have interacted with.
Ironically, even sometimes Scrappies Roll and GutsMan go wasted due an ironic failure to connect ideas between games. Battle Network 5 indicates healing powers are uniquely qualified to negate dark power, and Roll's special move "Roll Arrow" specifically destroys battle chip data; by rights, that should put her in a unique position to counter anything even remotely connected to Nebula. Meanwhile, the Secret Boss version of GutsMan in Battle Chip Challenge (look for his BCC code in Battle Network 4) employs a strategy entirely based around using powerful chips that require holes in the ground — Geyser, Old Wood, Magma Dragon, and God Stone. If he used those chips in the main series, where one of his specialties is putting holes in the ground, he'd be terrifying.
Operate Shooting Star features a time-traveling villain and a cross over with the sequel series, Star Force... for one scenario that basically amounts to playing tag. Otherwise it's just a port of the first Battle Network with a handful of new features.
Battle Network has more than a few Navi incarnations of reploids running around. We could have had Zero make an appearance in Battle Network 6, interacting with Colonel and Iris.
On the subject of Reploids, there was a missed opportunity to have Cyber Peacock appear in this series. Don't tell me he wouldn't fit in with the setting.
In the fourth game Lan travels around the world, meets all sorts of people and with their support faces an entity that claims mankind must be purged because of a few bad apples. Unfortunately, this is all presented as a very unsatisfying Random Events Plot.
NumberMan and Meddy are usually regarded as the most useless members of their respective teams, having impractical charge shots and equally gimmicky special chips. Their Order Point commands aren't much better either, with NumberMan's not liberating the Dark Panels it scans and Meddy's demanding two separate battles to liberate a line of Dark Panels between two clear ones. Overall, they are just vastly outclassed by their other version's counterparts, who have much more valuable abilities and an Always Accurate Attack for Charge Shots.
Competitively speaking, Aqua Soul in the fourth game is considered utterly useless. When it came back as Spout Cross in the sixth one, it was thankfully Rescued from the Scrappy Heap, thanks to a much stronger selection of Water chips.
Dark chips in the third game. While they didn't have any cost that prevented them from being worthwhile like in the later two games, they still had a few serious drawbacks. First, they required you to either set up a Hole tile on your side of the field (which required either useless chips that spawn one or using Darkman chips - locking your folder at least to the D code if you wanted to be consistent) or using a big program obtained by Bug Style to let you use them whenever. While this is bad enough on its own, all the dark chips were also giga chips. This means they had to compete against the Game-Breaker chips that are Folder Back and V5 Navi chips that had no setup needed. Though that said, they were still good compared to...
Dark chips in the fourth and fifth game, as well as dark-aligned chips. Dark chips generally lack the power required to make their permanent HP reduction useful in battle, and BN5 had the far better useful Chaos Unisons to use the chips anyway. Dark-aligned Megaman also had a second Last Chance Hit Point that also had Dark Mega take the wheel for about ten seconds that is completely random in its usefulness, which is a neat gimmick but nowhere near as consistent as the content it locks out. This ends up affecting the dark-aligned chips, as while they're better than their light-aligned chips (Static blows Tornado out of the water, Muramasa has proven itself in the earlier games, etc.), they aren't really that worth it for the price. Amusingly, they aren't this in the Japanese meta, where you're just as likely to see a dark player as a light player. The reasons for this are the previously listed dark-aligned chips, the emergency Darksoul, and either for emergency utility (four) or being able to use offensive dark chips that would suffer from Poor, Predictable Rock if used with Chaos Unison like Drill and Sword instead of utility chips like Thunder or requiring setup like Search (five).
Tough Act to Follow: While Battle Network 4 already had a bad reputation due to the Random Events Plot (and a few other problems...), it was considered subpar and below average compared to how highly regarded and praised Battle Network 3 is.
Unintentionally Sympathetic: The Heelnavi who wants to delete the Mettaur at Mettaur Village in the fourth game. While yes, Mega is right that they aren't doing anything at the moment, they're still viruses that Navi are programmed to delete and could even unintentionally cause problems because they're, y'know, viruses. Even with the incredibly humanlike characterization that game had going on with netnavis as a whole, he had a valid point and was deleted for this attitude (albeit in self-defence by Mega, as the Heelnavi attacked first).
Values Dissonance: Dishwashers actually aren't as common in Japan as they were in North America, which is one reason why Mayl and Mari's excitement over the dishwasher comes off as Narmy.
Values Resonance: Put yourself in Sean's shoes for a moment - There's nobody around you can relate to, you're stuck with cruel relatives (In his case, because his parents died), and the only people who you can relate to are online. Over ten years after the game was made, this still holds true to many people across the world.
One of the series recurring themes is cyberterrorism. While not invented by this particular series, Battle Network demonstrates objects being hacked and putting people in danger, government databases being hacked by terrorists, remote-controlled weapons going haywire, and crimes being ordered across the world with only the push of a button. In the 2000s, such a concept was still being thought of as fantastical. In The New '10s, technology and the Internet have developed to such an extent that many of the attacks depicted in Battle Network became reality (corporate & government databases now get hacked on a large scale at an almost annual basis), and cyberterrorism and cyberwarfare are constantly discussed in the media and by national security strategists.
A commentator has put this in an unusual light: In the 2000s, the series was a rather Saturday-morning cartoon esque series and made for great Snark Bait due to the obvious stupidity of adults. Unfortunately, ten years later, now many of the events within the series are plausible, even the stupidity of the adults. Nobody's laughing now.
Serenade. Any debate about his/her gender has a very high chance of turning into a flamewar. While Capcom themselves later on confirmed the cop-out that Seranade is a perfect being therefore transcends gender, most people ignore this as a result.
In the fifth and the sixth game there is usually only one or two of the kind random fat NPC that stood out among others and can pass off as either a male or female mostly caused by said NPC's pink shirt, hair curls and lipstick-like mouth. It was eventually revealed from some dialogues that the fat NPC is actually male.
Villain Decay: ShadeMan in the transition from the fourth to the fifth game. After being gunned down by a Pile Driver in a lategame sidequest thanks to Django, he went down from being an Invincible Villain that can only be damaged by Dark Chips to a damageable, but still difficult for a boss. That's fine and all, but then he was nerfed to a rather easy boss in 5 and demoted to the second Darkloid you face instead of a recurring threat and just below LaserMan in the Nebula ranks. His chip code was changed from X to S in the fifth game (Do note that the chip code X is usually exclusive to Infinity Plus One Swords, such as chips associated with Final Bosses and Bass).
Vindicated by History: Battle Network was rather divisive back in the day. While not quite to the Mega Man Legends extreme, the series usually had a few camps, those who liked Megaman Battle Network, and those who wished Capcom would have put more resources in developing the Megaman X series instead. Now, the series is looked upon with fondness and nostalgia - its Values Resonance, Campiness, the riff bait that is 4, as well as its still-to-this-day unique Fight Like a Card Player systemnote A game called One Step From Eden is being developed with a similar system, but it's very clearly inspired by the series to the point MMBN's speedrunning community include its demo in their marathons have made people look on the game with more forgiveness.
Around the early 2000s, Megaman in general was seen as an outdated relic that should have been left in The '90s thanks to a few entries being rather forgettable and Battle Network was swept up into the hate. At one point, someone asking about Battle Network at E3 was booed.