Ledge Bats

"Count Nefarious Vile, who has recently conquered the world with his army of monsters, demons, and those flying things that always knock you into pits when you're trying to jump."

—Press Start Adventures

Every veteran gamer knows what it's like: You're jumping across a series of platforms... and then you spot an Airbone Mook, maybe a little bird roosted on solid ground on the other side. There's a pretty good chance that the bird will completely spook and defend its terrain the moment you try to cross the last gap. Although your HP would be hardly worse off for what Collision Damage it can inflict, the main threat is that it'll also knock you back quite a bit.

If you're really lucky, you may land back on the platform and get another chance to try again. But far more likely, you'll get knocked off these ledges entirely, usually leading to:

A fall into a Bottomless Pit, Spikes of Doom, or anything else that costs you a life.
A fall down a non-lethal Bottomless Pit, or else to the bottom of the area, forcing you to climb all the way back up and try again.

Ledge Bats are the most infamous subspecies of Goddamned Bats by far, named for the bats in the Castlevania series that are quite prone to this. While naturally most at home in Platform Games, any game with pits of any kind (but especially the bottomless kind) can qualify for this. If the main purpose or hazard of certain Mooks is bopping you off ledges and into said pits, then they're Ledge Bats. With some kind of ranged attack at your disposal, you may be able to dispatch the creature and make the jump safely - if not, you'll have to settle for striking it down in midair by carefully timing your attack.

Not to be confused with those giant bat-like things you see on building ledges.

Examples of Ledge Bats include:

In addition to the bats, the original Castlevania also has Medusa Heads and crows.
The Scott Pilgrim vs. the World game features hordes of flying bats and Medusa Heads which fill the exact same niche, likely as a shout-out to Castlevania.
The Fission Metroids in Metroid Prime end up being this - the area you find them in requires a lot of platform climbing, and they are quite powerful and difficult to kill without Power Bombs (which you must stand still to use). Worse still, they eventually respawn.
- Fortunately, Fission Metriods stay still for several seconds to divide. Unfortunately, they're invulnerable for that time, and afterwards there are twice as many chasing you. Whether stunning them and running is worth it is a personal decision.
Every goddamned thing in the Ninja Gaiden games, with a special mention to the birds in the NES Ninja Gaiden trilogy.
The Legend of Zelda franchise ended up dealing with these surprisingly early.
- Zelda II: The Adventure of Link has Aches, Moas, Myus and Ras among the various enemies that are most dangerous around cliffs and ledges.
- The Legend of Zelda: A Link to the Past introduces Hardhat Beetles in the Tower of Hera and Death Mountain caves, who have thick enough armor to send Link flying back on contact, even when attacking with the sword. Naturally, there's also Bottomless Pits and other such drops in the area which can cost Link hearts and/or time spent climbing back up (and also means enemies will respawn as well). The boss of the Tower is Moldorm, who could only be hit safely in its tail and speeds up as it takes more damage. Hitting it in the body segments or letting it hit you bounced you back, potentially off the boss arena and down at least one floor - which meant doing the entire boss fight over again! This earned him the Fan Nickname "Trolldorm" among LTTP speedrunners in particular.
- Moldorm reappears in The Legend of Zelda: Link's Awakening, where it is fought on a smaller platform. The Evil Eagle in the seventh dungeon also flaps its wings to blow you off the tower, forcing you to re-fight it.
- Hardhat Beetles return in The Legend of Zelda: Oracle of Seasons, serving a similar role.
- The Legend of Zelda: Tri Force Heroes has Prankster Poes, whose heads and faces vaguely resemble those of the Links. Prankster Poes primarily spawn on large platforms, where they will quickly try to sneak up on one of the Links and toss them off the platform, and take several hits to defeat.
Throughout the Mega Man series are enemies who will jump out of Bottomless Pits, stall, and fall back in. If you are moving at top speed you will jump into one and recoil into the pit. Go play Mega Man 10 and start Commando Man's stage. They're all over the place.
This perfectly describes the behaviour of Banjo-Kazooie's 'Big Cluckers', birds which pop out of holes in the wall to hit you with their peckers and knock you off ledges in the final level. The designers even included a progressively more difficult gauntlet of ledges guarded by these. Earlier levels have eels (and in one level, skeletal eels) popping out of grates, but not with the same frustrating skill level as those cluckers.
- In the second game, there are clamp monsters that snap out of the wall when you pass near their hole. They usually only appear when you're grip-climbing across a crack, and getting hit guarantees falling.
Many La-Mulana enemies, from bats to Surprise Fish to Invisible Monsters, can and will push you off platforms and ruin your jumps. Perhaps the worst single example is a certain Mini Boss/Unique Enemy in the Confusion Gate which is called a bird but moves and looks like a giant bat and whose room is almost entirely made of narrow ledges.
A secret mission in Devil May Cry 4. You have to traverse disappearing platforms without falling, while under attack from several flying enemies at once who are exceptionally difficult to finish off quickly. And yes, practically ANY hit will knock you off.
- Mercifully, you can just step onto the first ledge so that the enemies will spawn, then step back onto the permanent starting platform and deal with them, leaving you free to navigate the floating platform maze without having to worry about being knocked off.
The pink Koindozers from Donkey Kong Country 3, mooks who all carry large shields with which to ram you off cliffs. The good news is, they only appear in one level in the game. The bad news is, they're all over That One Level. You can't kill them, just avoid them—and it gets pretty difficult to time your jumps properly so that you land safely on top of their shield rather than right in front of it at perfect bulldozering range—suggest that the good people at Rare do something physically and anatomically impossible with their mothers, and never play the level again.
I Wanna Be the Guy has the Medusa heads from Castlevania (which temporarily turn you to stone and knock you backwards), as well as the red birds in the graveyard (which push you around randomly). It's worth noting that these are the only enemies in the game that don't kill you with one hit.
Several mooks in the Metropolis Zone in Sonic the Hedgehog 2 function as this.
- Almost every long stretch of running and boosting or blind jumps in Dimps-developed Sonic games ends in you running into a badnik.
Bug!! features a few of these, especially one area in Splot where you had to jump from small platforms platforms with enemies on them.
The Oddworld 2D platforming series makes a habit of placing insta-kill bats near ledges, either to tell you to find another path or to take a leap of faith. And the game doesn't even tell you that these bats are deadly. Then again, everything kills Abe in 1 hit anyway.
Airborne enemies in Journey to Silius typically appear in areas with bottomless pits.
Super Mario Bros. (video game):
- Some of the cheep-cheeps in world 2-3 and 7-3 appear from below just when you're about to cross a pit, or dodge some other enemy. This can result in an unwanted goomba stomp which will send you right into the pit or into the face of another cheep-cheep or koopa. (It would be much less of a problem if the game had already implemented the Goomba Springboard like later Super Mario games.)
- Some of the later levels have bullet bills appearing out of nowhere at random y positions. If you're not careful you can be hit by one in the middle of a jump, which will either kill you directly or foul your jump.
- The Bullies in 3D platformers of the Super Mario series. Their only job is to try to knock the player off the platform they are standing on.
SuperTux castle levels often have rotating flames placed around small platforms above pits. Even with Big Tux, jumping into one of them is often lethal because it fouls your jump physics. After taking a hit, you will likely miss the next platform and plummet into your death.
- Short fuses rely on Knockback to damage the player. However, due to their lack of auto-turning behavior, they can only cause problems in a confined environment; otherwise you just need to wait until they walk off their platform.