Awesome Moments: The final boss of the second game, the Valkyrie Tank. Aside from the fact that it's a full-fledged WWII supertank, the battlefield is a burning arms facility at the center of Lance's empire. The Valkyrie Tank itself has a giant cannon called the Omega Lazer, which comes with a devastating charged attack. There's at least four different kinds. The best part is that you fight against Lance himself, decked out in his Nazi uniform, looking as intimidating as a human final boss can be. The ONLY human final boss, so far.
In 3, the Clay enemies. They're each immune to numerous elements, come in large groups which are almost never all vulnerable to the same attacks, and one of the later ones can cast healing spells. They are, however, all vulnerable to Lance's bomb element attacks. Thankfully, 4 toned them down by a lot.
In 4, there are quite a few in the factory. The Satellite dishes can cause Siphon on all your party members, locking them from using skills. The Laser turrets charge for one turn, the next turn they fire a big laser that will more often than not kill a character. Fridge turrets will pull a wet-freeze combo, landing status effects irritatingly often, while the rest of the enemies whale on you, and since we're dealing with bruisers with a taste for lightning here, getting hit while frozen or wet will most certainly cut a good chunk of your lifebar. The Drill Golem enemies hurt like no tomorrow. Did we also mention that these three enemies have TONS of health and take a long time to kill? Oh, and the Defender from the first game comes back, and it is a bruiser. Suffice to say this is especially bad during the boss battle.
Mage Dogs heal and buff allies, drain your characters MP and generally come alongside some really tough enemies. They also fully resist Dark and Holy and have no real weaknesses. Thankfully, they are vulnerable to Syphon, which confines them to basic melee. Mage Birds are annoying for many of the same reasons. They have pretty much no offensive abilities, but just like Mage Dogs they heal and buff allies and steal your mana... and even worse, they also have a 50% resistance to Syphon. Thankfully, like many flyers, the Thunder element makes quick work of them.
The Jellies of Bullet Heaven. There's a specific orange type that produces a different type of homing bullet than the purple butterfly-wasps. Said bullet chases you... in staggered steps. It's a pain to dodge, and really hard to fool.
Ear Worm: The Rave v2 theme that is used for minigames in the third game. The other tracks are pretty catchy too.
Ensemble Darkhorse: NoLegs tends to be popular among the fans. People even ask if he's going to be a playable character (and not just for the minigames).
NoLegs was Promoted to Playable in the Bullet Heaven games and will finally become a fully-fledged party member in the upcoming EBF5.
Even Better Sequel: Every consecutive sequel. The first is just a plotless battle against wave after wave of enemies. The second is similar, but with more story and improved battle mechanics. The third is a fully-fledged RPG with a world map to explore, and the fourth is similar but with even more secrets and items, better mechanics, an additional character, a non-linear map, and more World Building. Then there's the fifth game, with updated art, a more polished design, a new weather mechanic, the option to catch foes like pokemon, and NoLegs is finally gonna fight alongside his comrades. Just goes to show how far the series has come.
The Tera Drill spell does ridiculous amounts of damage to enemies with defensive buffs. Buff attack on whoever has it and even Akron goes down relatively easily.
In the second game, getting Matt to learn Mana Leech. Almost any attack in which his sword makes contact with an enemy will give him between 110 and 130 mana for free. Legend, his strongest physical attack, only costs 90 mana. Throw in a few Counter abilities, and enemies will be actively feeding Matt mana points.
If Matt equips the Rune Blade in the fourth game, and forges it to the max level, AND if you give Matt most/all of the ham items to buff his attack, you can regularly attack enemies with skills that cost MP and more often than not, your MP will be filled up basically automatically. Also, the max level of the Rune Blade basically guarantees that Matt will syphon his targets, and makes him completely immune to be dispelled and syphoned himself. The Rune Blade also boosts the damage of holy skills. Not only that, but he's just about guaranteed to counter, and he may casts a powerful skill called Glitter regularly, which is again, boosted by the sword itself.
In Bullet Heaven 2, NoLegs has the Shooting Star sub-weapon. It fires continuously in place, lasts much longer than any non-toggleable weapon, and you can have several of them active at once (unlike the toggled weapons, where you can only have one at a time). By picking up a diamond or heart to recharge your weapon at the right time, you can end up firing nine streams of bullets at once counting your primary weapon. You can either scatter the Shooting Stars around to hit everything onscreen or concentrate them in one spot to deal obscene damage - bosses can lose half their health within a second to the latter.
Goddamned Bats: The crows. They have high evasion and an accuracy-lowering attack. If all of your party gets debuffed, they'll take a lot longer to defeat.
There's also the robot fish in the factory in EBF4. They have a move that buffs their evasion, but the most annoying part is that when you kill them, they always release a missile attack that can stagger you. The only way to avoid this is to kill them last/all at once and end the battle (or wave) so the missiles won't land.
Pretty much every Airborne Mook in the platformer spin-off, Adventure Story, but especially the flies. What makes them especially aggravating to deal with is all the backtracking you'll have to do after they knock you off a platform, or mess up your jump while you're in mid-air.
The first game, after you finish the slimes (which, unlike the other mooks, you have to get through four waves instead of two) and get to the first (mini?)boss, where it then becomes a challenge. The second game averts going through four rows of the basic enemy by throwing in a red bee.
In EBF3, the entire series evolves from a simple Turn-Based Combat-only RPG into a fully-fledged one, with a world map!
Heartwarming Moments: If you return to Greenwood Village after enough story events, some of the villagers will give free items to Anna.
Idiot Plot: In EBF4, Anna and others know how powerful the game's MacGuffins are. And yet no one stood guard over them. Considering they were stolen by the weakest enemies of the game, one must wonder if it was subtly Played for Laughs.
Also, if Anna didn't suspect Matt as the culprit entirely based on Fridge Logic, the original trio wouldn't have been dragged into the plot in the first place.
Mascot Mook: The Slimes (or Slime Bunnies), and the legless cats.
In EBF4, Matt is somewhat Oblivious to Love, which secretly disappoints Natz. It's explicitly shown that he returns her feelings to an extent, however.
Likewise in the fourth game, early on Lance tells Matt quietly that if he doesn't want Natz, Lance will take her for himself. Matt replies that Lance left her behind and split the party like a dumbass.
To throw in a little Les Yay on top of all that, Anna begins a conversation regarding Natz's breast size and it's applicability to combat. Natz cuts off the conversation quickly, noting Lance is quickly becoming a drooling pervert on the subject, while Matt is trying to avoid noticing the situation altogether. This is disappointing for Anna, who was about to ask to touch her breasts.
That One Achievement: Some of the minigame-based medals in the original EBF3 are very difficult to obtain, to the point where the Steam update lowered the score requirements for each minigame.
That One Attack: Cosmic Monoliths have one: every 3 rounds, they use an attack named Doomsday. It is a much stronger version of what the party can do by using Dark Runes, and it starts off with a weak beam trailed through the ground, dealing low damage to the party — THEN the actual attack kicks in, dealing MASSIVE damage to the party, capable of taking out anyone with no dark resistance, even at level 30. To top it off, Doomsday hits the entire field AND COSMIC MONOLITHS ABSORB DARK!? And it goes From Bad to Worse in the final medal area, where one of the battles is with all 3 monoliths. Combined, they're harder to kill than Akron himself. It is better to leave Cosmic for last in this case, as the other 2 monoliths do NOT absorb dark, and will be damaged by Doomsday — but since all 3 monoliths are incredibly powerful, it is so much more likely to kill you.
On top of all the instant death attacks in EBF3, Doomsday counts too, and is a definite That One Attack; if you don't have sufficient dark resistance, you will die.
In EBF2, it's possible (on higher difficulties, mind you) for the Valkyrie Tank to summon two nukes when one is already enough to wipe out an unguarded party.
In EBF4, mage dogs, mage birds, and clay idols can use an attack that does no damage but drains most of a character's MP, leaving them with enough mp to use maybe three moves. This becomes less annoying at New Game+ levels, where the remaining MP is usually enough to finish the battle. If the attack happens to be used once, when the enemies with this move tend to show up in groups!
The defender has a single-target physical attack that hits twice, but one hit can easily hit for most of the target's health, even with maxed buffs!
Doomsday makes its return in EBF4. It got weaker in some ways, such as requiring a turn to charge, not healing the monolith, and not being preceded by Flare. However, it's now only 75% Dark elemental, which means 100% Dark resistance isn't enough to nullify it.
Rainbow Rafflesia has a healing skill that removes status effects, buffs its M. ATK and M. DEF, and applies maxed Bless status. This means the player can't get rid of its buffs, especially if it uses the skill again before Bless expires.
The same boss also has a Non-Elemental rainbow attack that hits one player for absolutely ludicrous damage, enough to One-Hit Kill several times over on higher difficulties. To make matters worse, it also stuns the target if it hits without actually killing!
Dark Matt's Annihilate does a massive amount of damage, when the exact same Limit Break does next to no damage when used by Matt.
Possibly justified due to Matt's Annihilate having a higher chance to instantly kill compared to Dark Matt's.
Dark Natalie's Black Hole does not do damage to her, while when Natalie uses it the party takes a very small amount of damage with a chance of instantly dying. Note that Dark Natalie, like all bosses, is completely immune to instant death. Fortunately, Dark Natalie doesn't herself take damage from Black Hole either, since she absorbs darkness.
Dark Lance's Nuke does not burn him, while Lance's Nuke burns the whole party.
Dark Lance's Unload and Dark Matt's Legend don't apply ATK down or Tired on them respectively, allowing them to spam these moves without consequence.
The enemy version of Supernova used by Dark Natalie and the Destroyer don't burn or otherwise hurt their side.
Unpopular Popular Character: Lance, especially going by his depiction in EBF4. While the main characters hate him, he's one of the fanbase's most popular party members. Some fan fiction works faze out most of his negative aspects entirely.
In EBF3, it's entirely possible to walk into a bonus area, save, exit, visit the medals page, and delete all your medals! This causes the NPCs that guard the bonus levels (until you have sufficient medals) to reappear, blocking your exit instead of your entry! That's right. You can trap yourself in a bonus area unless you have a spare save from the same playthrough.
4 has the Battle Mountainice puzzle, which is difficult enough by itself, even with the hint (The secret is to line the ice blocks in a row). It's actually possible to block yourself in the puzzle! Hopefully, unlike what's in the link, you'd be observant enough not to save in the middle if you've blocked your exit on all sides!
The second game. With a "giant mutant penis" (the sandworm is referred to as that in the scanbot entry) that vomits blood, you would think that it would get a higher rating than "Anyone" on Newgrounds. Even weirder because the original game was "Teen".
Early in the third installment, Matt says: "I used my fapping arm for that attack!" Also, innuendos of tentacle rape and the return of the giant mutant penis, all Played for Laughs.