You’ve heard the saying “bigger is better,” but that is not always the case when it comes to video-game villains. The following baddies are short on stature but represent a big hurdle for the heroes who must fight them.

Goombas (Super Mario Bros.)
This is the very first enemy Mario encounters in Super Mario Bros., and countless gamers experienced death at the hands (legs?) of that one Goomba that trots into the screen at the beginning of stage 1-1. While not very smart, these walking mushrooms are so prolific that one will eventually get you.

Headcrabs (Half-Life)
These alien parasites can control humans by latching onto their heads and turning them into mindless zombies. Their small size and agility make them a big threat for Earth’s resistance and a formidable addition to the invading Xen army. If Gordon Freeman could talk, his first words would probably be “get these f***ing headcrabs off me!”

Metroids (Metroid)
In space, no one can hear you scream -- especially if you have a Metroid sucking your life force through your head. Their energy-absorbing ability has made them the prime target of Space Pirates, so bounty hunter Samus Aran has been pulverizing these small jellyfish-like creatures throughout the galaxy. Invulnerability to almost all forms of weaponry and the ability to reproduce asexually make Metroids one of the most dangerous life forms in the universe.

Crows (Resident Evil)
I don’t trust crows since I watched Alfred Hitchcock’s The Birds, and the undead ones from Resident Evil have only made my animosity for them grow stronger. The T-virus has infected everything in Raccoon City, and the crows are no exception. They’re small but always attack in packs. Crows probably won’t kill you, but their diminutive size and erratic movements make them hard and frustrating targets.

Flood “infection form” (Halo)
I hate the Flood. They are gross-looking, tough to defeat, and they multiply rapidly. The “infection form” is the worst because of their quickness and minuscule size. They pop like balloons with a single shot, but a small pack of them can kill you in seconds. If the Flood get to a corpse, whether human or Covenant, they can reanimate and control it, so make killing these little bastards your top priority.

Medusa heads (Castlevania)
When not making an appearance as a boss, Medusa can be seen as a floating head which annoy the hell out of the Belmonts and fill gamers’ hearts with murderous fury. Snakes don’t fly, and neither do severed heads, so why do… You know what? Forget it. Medusa heads are the number one cause of vampire hunter deaths as well as the root of Indiana Jones’ ophidiophobia (fear of snakes). They share a tie for first place with Ninja Gaiden's hawks for game enemies I hate the most.

Rabites (Secret of Mana)
Cute, furry woodland creatures deserve death by sword too, especially if they’re gnawing at your ass. The Seiken Densetsu (Mana) series features a flood of these adorable, fluffy, rabbit-like things, and I just want to hack them all. Rabites do little to help you level up and drop crappy items, but it’s so satisfying ripping them apart! They couldn’t be farther away from being an endangered species, so let me have my fun.

Slimes (Dragon Quest)
It’s impossible to dislike slimes; just look at them: water-drop shape, mesmerizing eyes, and that perpetual smile. They’re also weaker than the Washington State football team’s defense, so they pose no threat whatsoever...or do they? New, more powerful versions of slimes have shown up in recent Dragon Quest games. The King Slime, for example, can even cast magic spells and will give you more than one experience point and gold coin when defeated.