Goddamned Bats

We can't stop here. This is Zubat country.

"Every first-person game seems to have these tiny little enemies that hop at your face, are hard to hit and, worse of all, are unsatisfying to kill."

—David Wong, Cracked.com

"Why do so many games have so many fucking BATS?!"

—James Rolfe, The Angry Video Game Nerd

They're probably not going to kill you like a extremely overpowered mook, but they're certainly going to harass you and slow you down.

Almost every video game has them. These are the enemies that are just a speed bump, even if they are not outright dangerous. They're not difficult to defeat, but because of the frequency with which they appear, they can become a significant hindrance to the player.

They're the goddamn bats, man.

A key trait is that they generally don't pose too large of a threat on their own; they're more annoying than deadly. When an enemy starts posing an actual threat, then it's a case of Demonic Spiders and, in extreme cases, the Boss in Mook Clothing.

Note that this designation applies to any type of non-threatening enemy whose purpose is to stall and harass the player. Goddamned Bats are common in Platformers, where they enjoy disturbing precision jumping.

Common traits of Goddamned Bats may include but are not limited to:

Evasive abilities that allow them to dodge attacks, making them difficult to actually hit.
Higher encounter rates, appearing more frequently than other enemies in the same area and/or very good at detecting the player.
Attacking in groups so that it takes longer to kill them all. Often involves a Mook Maker generating new copies, or a fast respawn rate.
Difficult to escape from. Maybe they block your retreat, maybe they can move faster than you, etc.
Can fly, making it difficult to hit or target (or they may just be a lot shorter than your character).
Appearing in tricky situations where they can distract you; Ledge Bats are an infamous type, whose love of Bottomless Pits has sent many a videogame character to their doom.
Self-destructs, damaging you as it does, and/or denying you whatever experience/spoils you could have otherwise earned from it.
Steals needed items (which you may or may not get back upon defeating them) or worse, eats or otherwise destroys needed equipment.
Can poison the player or apply another permanent effect, resulting in the player needing to use an item or run back somewhere for healing altogether.
Provides light or otherwise makes itself undesirable to kill, while still attacking the player like a rabid monkey.

Other following factors can contribute to a game having Goddamned Bats:

Player having relatively large health bar, reducing the enemies' relative threat (and thus the need to exterminate them quickly) -- even if it's just Scratch Damage, enduring repeated hits adds up.
In platform games, character flying backwards after getting hit.
If the game relies heavily on Respawning Enemies.
If the player has a weapon with limited attack range or can't shoot vertically or diagonally, making it difficult to engage the bats.
If the battle becomes disrupted by technical issues, like a Camera Screw.

Occasionally, Goddamned Bats can be a result of the setting; for example, a water level can inadvertently graft Goddamned Bats characteristics onto any enemy if the game has poor movement controls.

The boss version of this trope is the Goddamned Boss, who is an absolute pain in the butt to fight. For a Narrative Tropes version of this, you want The Usual Adversaries. For actual bats, see Bat Out of Hell. Do not confuse with the goddamn Batman.

Examples of Goddamned Bats include:

Video Game Examples

Non-Video Game

Anime and Manga

One Piece has a villain whose main method of 'attack' is to hide behind a cloud of regenerating shadow bats as hard as bricks and run away when his opponent's not looking. Cue the protagonist spending the entire fight wandering around the forest looking for his enemy.

Board Games

In the 1978 Avalon Hill board game Magic Realm the giant bats are among the most dangerous of all monsters. They are too fast to run away from or hit reliably, kill unarmored characters instantly, and wound to death those with heavy armor.

Live Action TV

Piranhas became this in an episode of River Monsters, in which Jeremy constantly caught piranhas, when he wasn't just having his bait stolen.
In Community, the hippies act as this when the group plays an important video game created by Pierce's elitist father.

Web Comics

Homestuck has IIIIIIIIIIIIIIIIIIIIIIIIMPS!!!!
- Which become Bosses in Mooks Clothing after Jade prototypes her kernelsprite.