If there’s one thing a successful survival horror game needs, it’s the scare factor. That sense of the unknown, of impending doom creeping up your pants leg. Franchises like Silent Hill and Resident Evil have developed an effective formula for this: keep throwing different kinds of hideous, lumpen mutate-o-demons at the player.

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Resident Evil, in particular, has brought us an impressive range of horrifying enemies. Most of the series’ bosses make us wonder just how the heck the designers managed to come up with something that ugly. Which are the most frightening and ugliest bosses in the franchise, though? Buckle up and let’s take a look!

10 Infected Bat (Resident Evil Zero)

Bats have long been associated with horror, with their nocturnal tendencies and the general air of Count Dracula that they give off. There’s just a vibe about them, a vibe that a hefty dose of the t-Virus absolutely does not help with.

The Infected Bat is a boss encountered in the chapel of the Umbrella Executive Training Center in Resident Evil Zero (a couple of them are also battled in Resident Evil: The Umbrella Chronicles). Gigantic versions of regular creatures appears as bosses throughout the series (such as Resident Evil 2’s Giant Moth) and they’re all especially uncanny, but the Infected Bat gets our first nod. Much worse still awaits us, though.

9 Ultimate-8 (Resident Evil 5)

You probably know this beast better as ‘that disgusting crab/tentacle thing you fight on the elevator.’ Tricell preferred to be a little more mysterious and scientific when naming their creatures, though, so this Resident Evil 5 boss was officially designated Ultimate-8.

Chris and Sheva encounter this super-creepy crustacean in the Uroboros Laboratory. It can be tough to take down and deals a lot of damage, but it has some convenient little glowing week points for the player to target. So that’s considerate of it. It’s certainly not a looker, but, again, there are much more memorable monstrosities in the series.

8 Neptune (Resident Evil)

As we’ve already seen, Umbrella’s scientists seem to have a penchant for making bigger, angrier, more powerful versions of existing animals. Giant bats and moths are more than enough to deal with, but the original Resident Evil’s Neptune creature (more specifically, the mother, which is fought as a boss) is probably the most terrifying of all.

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A huge, mutated shark, Neptune specimens inhabit the aqua ring. This is one of the most visually impressive areas in the Resident Evil remake and the monstrous shark was truly a force to be reckoned with. We can’t rate it any higher, however, because it’s just too easy to dispatch (via electrocution).

7 Garrador (Resident Evil 4)

Sometimes, the most frightening enemies aren’t the huge, inexplicable, mutated creatures, but those that are distinctly human. How did this friendly fellow get the name Garrador (Clawer, roughly translated)? Spoiler: by trying to tear its opponents several convenient new bodily orifices with its claws, that’s how.

These poor souls have been infected with the Las Plagas parasite, which has given them incredible strength and durability at the cost of their humanity. With their eyelids sewn shut, they cannot see, but their sensitive hearing soon allows them to locate Leon and try to tear him apart. The first Garrador is encountered as a mini-boss in the castle prison, where the player learns that the parasite in their backs is their weak spot. Formidable, but they can be swiftly dealt with by experienced players.

6 Nosferatu (Resident Evil: Code Veronica)

The Ashford family’s fortunes have always been closely linked to those of Umbrella (and the other major players in the Resident Evil series). As such, it’s no surprise that they’ve suffered all manner of ghastly incidents. Few suffered as much as Alexander Ashford, though, the man who would eventually become the monster known as Nosferatu.

The victim of cruel experiments performed by Alfred and Alexia Ashford, the twins he created, Alexander mutated into a hideous, vampire-like figure. In a classic Resident Evil battle-on-a-helipad situation, Claire Redfield kills the miserable creature in Resident Evil: Code Veronica. We’ve given Nosferatu the middle spot on the list because the poor soul is as wretched as it is monstrous.

5 Draghignazzo (Resident Evil: Revelations)

By the time of Resident Evil: Revelations’ release, the series had already brought us a whole menagerie of hideous creatures. What could Capcom do to bring us something new? Well, Revelations was largely set on a cruise ship, which opened up a whole world of hideous watery foes. Our friend the Draghignazzo, for instance.

This monstrous creature is loosely based on a shellfish of some sort (loosely enough to drop right off and roll under the couch, but the reference is just about there nonetheless). It’s a huge, towering creature that attacks Jill Valentine and Parker Luciani in the Promenade Hall, before they’re finally able to kill it on the observation deck. Menacing as it is, there are more iconic monsters to come.

4 Verdugo (Resident Evil 4)

Now, this was a set-up for a horrifying sequence: Leon has hit the elevator button, and it’ll be a moment or two before his ride arrives. In the meantime, he’s trapped in an enclosed area with one of the most formidable enemies in all of the sublime Resident Evil 4: the Verdugo (Executioner).

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Experienced players will know that this thing can actually be dispatched quite easily with the liquid nitrogen freeze/rocket launcher shatter maneuver, but without that, it’s wicked fast, darn strong and will take a heck of a beating before going down. The fight is really based around Leon simply evading the creature until he can escape in the elevator, and less confident players are advised to do just that. Still, the fact that it’s possible to easily defeat it means it has to miss out on the top three spots.

3 Nemesis (Resident Evil 3: Nemesis)

The Nemesis from Resident Evil 3

Resident Evil 3: Nemesis is the story of what happened to Raccoon City after the famous outbreak of the original game. In the wake of the incident, Umbrella need to eradicate anybody who witnessed the events in the mansion, so they deploy a new B.O.W. with orders to eliminate S.T.A.R.S. members: the Nemesis-T Type.

If you’ve ever played the game, you’ll know that this creature is absolutely relentless. The original Tyrant was one thing, but Nemesis would pursue you throughout the game, bursting through walls and ambushing Jill at the most inopportune moments. With its rocket launcher and the constant sense of dread it induced, the Nemesis really is one of the scariest enemies in franchise history.

2 William Birkin “G” (Resident Evil 2)

The recent remake of Resident Evil 2 was a lovingly crafted title that did justice to the original. While that’s great and all, we’re not sure that introducing the horror that is William Birkin’s “G” form to a new generation was the best idea. Brrr.

The term “G” refers to those unfortunate souls who have been infected with the Golgotha Virus. The most notable “G,” of course, was Dr. William Birkin, who had a cool, clear glass of Golgotha to save himself after the USS tried to kill him (when he resisted their attempts to take the virus from him). He went through a total of five different stages of mutation, each as dashingly handsome (in a hey, look at this gigantic eyeball in my shoulder sort of way) as the last, before finally being defeated.

1 Jack Baker (Resident Evil 7)

Of all the bosses we’ve taken a look at so far, Resident Evil 7’s Jack Baker is the most human of all. On the surface, at least. You might be wondering how he earned himself the top spot, then, but here’s the thing: that’s exactly how.

The series has brought us just about every kind of grisly mutant imaginable, but here was something new, a different kind of threat. This title is a very visceral, first-person adventure, and being pursued by this nigh-invulnerable enemy through a very real, very creepy house is enough to set anybody on edge. The encounter with Jack in the garage, after he dispatches the police officer through the head with a shovel from behind, is on a completely new level of unsettling. Once he gets in the car, that’s a real yikes.

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