Goddamned Bats / Shoot 'em Ups

• The Gradius series had Zubs that teleport onto the screen and will most likely kill you if you are not prepared for them, and some volcano stages have Erupting Rocks that will force you to the top or bottom of the screen.
  • The rocks in Gradius III AC's lava stage were more like Demonic Fireballs, they appear in large numbers, split into indestructible fragments when shot, and to make it worse, the passage gets narrow near the end of the level.
  • Salamander/Life Force (arcade version) had that ship that causes the screen to flash, potentially inducing seizures.
  • And the, er, demonic Option Hunter.
• Touhou Project has Lily White. In the ninth game, Touhou Kaeidzuka ~ Phantasmagoria of Flower View, she will randomly appear in both player's fields and rain down hell upon you for no reason other than she can. Sure, you can shoot her down, but she comes back a minute later. This is especially irritating when fighting Medicine or Eiki. Goddamned Lily.
  • Also, Orin, who makes her appearance in the 11th game, Touhou Chireiden ~ Subterranean Animism, as the Stage 4 mini-boss... twice (like Alice in Touhou Youyoumu ~ Perfect Cherry Blossom), then as the Stage 5 mini-boss... then as the Stage 5 boss... and finally as the Stage 6 miniboss. Whatever you have to say about Lily, at least she only stays for one wave. This bugger tails you through three stages, and only lets up when Hell's fires get too hot for even her.
• Metal Slug has Helicopters that constantly hover overhead and fire on you. On their own, they're not too bad, but they have a habit of attacking you while being backed up by tanks, soldiers with knives, and other such ground infantry, making it very difficult to kill them off due to the wave of attacks coming from both ground and air. It's even worse when they come in a row and start circling overhead, constantly raining down bullets everywhere. In those cases, at least, shooting the leader causes a chain reaction to take out the rest, giving a nice score bonus.
  • You know what's worse than the helicopters? The normal soldiers that throw fireworks at you. Despite having the same amount of health as other soldiers, the player can hit their projectiles, not only blocking your shots but also making the objects much more unpredictable to dodge. Add in the usual threats(including the helicopters) and you're all but guaranteed to die many times.
  • Bazooka soldiers tend to be positioned in hard to reach areas and can aim diagonally to fire at you. While they only take one hit to die, they're irritating to hit without a Slug or Heavy Machine Gun thanks to Denial of Diagonal Attack on your other weapons. Those descending via parachute also tend to be quick on the draw meaning that you'll have to avoid at least one bazooka bullet flying at your position if you don't shoot them immediately.
• Spheres of Chaos has black holes. Those which attract objects aren't too bad, but those which repel, are, making objects to go fly everywhere and player has to fly very close to them to shoot them due to their repelling force. This is especially bad with multiple black holes.
  • They also have Dodgers which are normal enemies with the ability to dodge player's fire, often making them hard to catch.
• Star Control II's Slylandro Probes. (Warning: Link contains the 'f' word.)
  • Fortunately, the Probes can be easily beaten for easy money if you have a Spathi Eluder, one of the best ships in the game.
    • The worst place to encounter them just HAS to be in Ur-Quan space. Especially the border. It is entirely likely you will be stuck in an impossible-to-escape series of sequential battles as more Ur-Quan and Slylandro continuously spawn.
  • During combat in any of the three installments in the series, asteroids play a similar role, straddling the line between a mindless environmental hazard and an active adversary. They are spawned constantly, most of them along random trajectories, but some are intentionally hurled at your ship to make things harder for you. They'll block your shots, push you into an enemy's line of fire, ruin your perfect maneuvers, and in the worst case push you straight into the planet (for massive damage).
• R-Type players hate Cancers with a passion. Why? Though extremely easy to kill (one shot from anything makes them dead), they home in on you while firing shots with near-perfect accuracy, and often (this is the kicker) come in on the left side of the screen. Unless you are powered-up, you cannot fire in that direction. Use your imagination...
• Space Invaders Extreme has Reflector Aliens, which bounce your shots off, Assault Aliens, which take two hits to destroy, the first making them fly down to kill you, Flipping Aliens, which turn on their sides to become harder to hit, and much more.
• Grakin Assault Helicopters and Mokum Assault Helicopters from Heavy Weapon. The former enters screen, and then it spams homing missiles on your tank. These helis have quite a bit of health, and they tend to come with other enemies, making them annoying to defeat. As for the latter? They're like the former, only with more health, and twice the missile spam. Gah.
  • S-34 Reflex fighters. Like the helicopters, they spam homing missiles but thankfully leave the screen. They're annoying because they sport Deflector Shields that absorb your regular shots (given that your regular weapon is a rapid fire Spread Shot, it happens a lot). When this happens it sprays out unkillable purple plasma shots in completely random directions while also making a rather irritating sound when they do so. It's a good thing said shields do not absorb your special weapons fire.
  • Another helicopter that appears alongside the Grakin and Mokum Assault Helicopters is the Czerk Light Helicopter. Unlike the two, this one forces you to move left and right to avoid their slow but irritating plasma shots. It becomes very annoying to do so, especially when they either have the tendency to corner you with several plasma shots or appear with the two mentioned helicopters which already makes three of them a complete pain to deal with.
  • Barskov Munitions Blimps. They're big, block most attacks meant for other enemies that are more threatening (such as Havanski Atomic Bombers and Romanov Attack Satellites), and then there's the fact that they blow up into a random shower of indestructible (unless you use a Nuke or Megalaser) shots when killed and the shower may be impossible to avoid depending on the spacing between the shots. Thankfully there's usually a gap in the shower but if you're really unlucky there might not be one and the shot sneaks through your defense orbs.
• Raptor: Call of the Shadows has Mooks, both airborne and grounded, fire aimed orange flak balls at you to make things more difficult. Individually, the shots are weak, but in numbers they can whittle down your shields and armor if you're lazy enough to not get out of the way. A large number of these Mooks will use these on you in the later levels and harder difficulties. Coupled with the tendency of Mooks to appear suddenly on the screen and blast you with more dangerous weaponry, and the flak balls are more likely to hit you since you're too busy avoiding to get hit by other Mooks while simultaneously trying hard enough to pick them apart for cold, hard cash to spend at the Emporium. The end-of-level bosses, including the Cores And Turrets Bosses, have these equipped as well so you can't afford to dawdle around.
• Done with actual bats in DownWell. If you don't kill them from above, they start flying after you. And you can't shoot upward.
• Event Horizon has its own fair share of Fragile Speedsters which are ridiculously difficult to shoot down, but Chrysalis is arguably the most annoying. Fast and light, it will bombard you with bullets which screw your motion, and knows how to use the recoil of its mass driver to easily dodge your fire. And being a Living Ship, it comes with a Healing Factor, so don't hope for taking it down by Death of a Thousand Cuts.

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