While the dense, mysterious overarching plot of Neon Genesis Evangelion drew viewers in, it was the weekly threats of the Angels that kept each episode interesting. Every time they tuned in, viewers would be looking forward to seeing what cool new designs the creative team had come up with.

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So, what makes a good Angel design? As well as overall effectiveness, some designs truly brought something particularly unique to the canon of mecha anime enemies, while others sent a shiver down audiences' spines. Taking a look at some of these unique designs, it's no surprise Shinji was reluctant to get in the robot.

10 Viewers Don't Get A Clear Look At Sandalphon's Design

Neon Genesis Evangelion sandalphon

Official art reveals that Sandalphon, the 8th Angel, has a great design with a lamprey-like mouth and bristled "hands" that add a truly creepy, alien quality to a relatively recognizable fish-like body.

Unfortunately, viewers of the original show never got to appreciate these details. Sandalphon spends most of the episode in an embryonic state, and even when it does "hatch," it's fought and defeated while still submerged in lava. This was a unique fight that helped to strengthen the bond between Asuka and Shinji, but it definitely wasn't the clearest to watch.

9 Gaghiel's Design Is A Little Fishy

Anime Evangelion Unit-02 Fights Gaghiel On Water

There are definitely some great design elements in the design of Gaghiel, the aquatic Angel who attacks the battleships transporting Unit 02 and Asuka to Tokyo-3. The sleekness of its body, along with its two-toned color scheme, suggests a manta ray, which is an interesting direction to take the design.

However, once it gets in the water, Gaghiel's design just isn't that unique. With its huge, shark-like jaws, it's a good sea-monster design, but not nearly as alien as something like Sahaquiel, Armisael, or Ramiel. It's more suited for Jaws than Evangelion.

8 Arael Is A Literal Interpretation Of An Angel

arael from evangelion

Appearing in episode 22, Arael is one of the most unique angels in the series. Not only is it the only angel never to enter the Earth's atmosphere, but its attack is purely psychological, attacking the pilots' minds rather than their mechs.

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Despite -- or perhaps because of -- this, Arael's design is a lot less surprising. With its glowing, outstretched wings, this might be the enemy who is closest to what an average person would imagine an "angel" to look like. It's certainly effective, but doesn't show the creativity of some of the series other designs.

7 Sahaquiel's Design Plays With Color & Shape

sahaquiel from evangelion

There's almost something cartoony about the 10th Angel, Sahaquiel, with its huge eyes, gaudy color scheme, and protrusions that look like something like a cross between flower petals and a sticky hand.

It's exactly this strangely bright design, though, that makes Sahaquiel so effective as an enemy. It contrasts brilliantly with the tension of the episode, as the characters wait for it to fall to Earth and plan a desperate, seemingly impossible mission. The sheer scale of the Angel also helps take the design from absurd to terrifying as the sight of that enormous eye looking down on Earth demonstrates.

6 Armisael's Design Is Truly Heavenly

armisael from evangelion

The effectiveness of Armisael's design lies in its simplicity -- it's a single glowing ring of light. And yet, even this incredibly minimalistic design is, in fact, a combination of two ideas: the image of the halo, which fits perfectly in with the show's religious motif and the idea of "Angels," and the double helix structure of DNA, which hints at this Angel's ability to enter and alter the bodies of humans and Evas.

It can't be denied that the design is somewhat weaker when Armisael unravels itself into its attacking form, which is just a single, glowing thread, and thus loses those two layers of imagery. The design team has done their job, though, and left the audience with a bold, multi-layered image that sticks in their mind all through the battle.

5 Ramiel Has A Seriously Sharp Design

ramiel from evangelion

Like Armisael, Ramiel proves that sometimes the simplest designs can be the best. It's a huge, angular, completely featureless geometric shape that doesn't even look like something organic. This makes it seem even more alien than most of the other Angels, and thus all the more threatening. It's impossible to know what to expect from something that doesn't even seem to be alive.

But perhaps the most unsettling thing about Ramiel is that it is alive. After it is defeated, there's a shot of NERV dismantling its body, where viewers can see red blood underneath the other shell. Creepy.

4 Matarael's Design Has Viewers Reaching For The Bug Spray

matarael Neon Genesis Evangelion

With its massive, spindly legs and comparatively small body, the 9th Angel, Matarael, closely resembles a harvestman or similar arachnid. This scaling-up of an already creepy creature works perfectly, making viewers shudder as this Angel scuttles through Tokyo-3.

And then Matarael's "face" is revealed. Its huge eye, which appears even more human due to the fact that it secretes its corrosive acid through "crying," provides a strong contrast to the insectoid appearance of the body. Human-like emotion and a terrifyingly inhuman form seem to combine to create something truly uncanny.

3 Sachiel Starts Off The Series On A Terrifying Note

Anime Evangelion Sachiel Air Strike Attack

As the first angel who appears in the series, it's important that Sachiel makes a big impression. It's no surprise, then, that the show's creators obviously poured a lot of work into producing a fantastic, iconic design.

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Sachiel's design is one of the most humanoid of all the angels, which is a smart move for the first episode -- a design that was too abstract might have put some viewers off. But details like the disproportionally long arms and the blank, soulless mask of a face plunge this design straight into the uncanny valley. Add in the creative way that Sachiel's blades are propelled through its arms, and the result is an intriguingly creepy design that provided some great action for the first episode.

2 Leliel Has Two Designs In One

The Angel Leliel looms over the city in Neon Genesis Evangelion

What's fantastic about Leliel's design is that it consists of not one, but two concepts that are both well-executed and complement each other perfectly. The huge, spreading shadow is classically creepy, speaking to viewers' natural fear of the dark, while the garish, optical illusion-style patterns on the floating body provide an element of surreal horror.

This body is, in fact, just a shadow cast on the real world's dimension by the Angel, which has created a dimension of its own. The audience can really believe that this is an interdimensional being. Subtleties in the black-and-white patterns create shapes that look almost like eyes and a fanged mouth that have been distorted as if pulled into a wormhole.

1 Tabris, A.K.A Kaworu, Is As Pretty As He Is Creepy

Kaworu smiling Evangelion

Yes, the best Angel design goes to the one who doesn't look like an Angel at all -- Tabris, the 17th Angel, who is given the form of a human and the name Kaworu Nagisa in order to infiltrate NERV.

Kaworu's design might be considerably less alien than his fellow Angels, but its success can't be denied. His classical bishonen looks are made subtly otherworldly by his silver hair and red eyes, lending him a mysterious beauty that would make him become one of the franchise's most popular characters.

NEXT: Evangelion: The Strongest Angels, Ranked