With Avatar 2 on the horizon, film fans are reminded that when it comes to modern movie making, the sky is nearly the limit for creating fantastical beasts and beings that look believable to audiences. The technology has come a long way over the last couple of decades, with almost every major motion picture utilizing CGI to ensure that viewers are completely engrossed in what they are watching.

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While not every movie gets this right, there have been some that created amazing-looking monsters and creatures with jaw-dropping special effects. From science fiction, fantasy, romance, children's animation, and more, some CGI creatures and monsters are just downright impressive.

Dementors (Harry Potter)

A dementor attacks Dudley Dursley in a scene from Harry Potter and the Order of the Phoenix

There is always something exciting about seeing a fictional monster that has been described in a book appear on the big screen. J.K. Rowling described the Dementors in Harry Potter as being terrifying beasts that smell of death and decay. They glide around ominously, and the only part of their flesh that is ever seen is their rotting hands.

The CGI versions of the dementors in the movies hit the nail on the head, and then some. Not only are they as terrifying as the books describe, but the way their hoods cling to their skeletal form adds a chilling factor that audiences didn't know they needed.

Davy Jones (Pirates Of The Caribbean)

Davy Jones in Pirates of the Caribbean

Pirates of the Caribbean: The Curse of the Black Pearl utilized CGI in 2003 for its undead pirates, to great effect for the time. However, the true magic came with its sequel in 2006, Dead Man's Chest. In this movie, Davy Jones himself is introduced, played by Bill Nighy.

This version of the Pirate Lord of the Depths is portrayed as being something between a man and an Octopus.  Nighy wore no prosthetic make-up for this part. Instead, he was completely clad in a green screen body suit and motion capture devices so that the character of Davy Jones could be built around his performance using CGI.

Gollum (The Lord Of The Rings And The Hobbit)

Gollum looking up in TLotR

The Lord of the Rings: The Fellowship of the Ring was released in the early days of advanced CGI, so the work that was done on Gollum was extremely impressive. Andy Serkis, who was perfectly cast by Peter Jackson to play Gollum, wore a green screen suit and his every movement was arduously animated over with Gollum's skeletal frame. What made the character so believable was Serkis's facial expressions, which were still very recognizable.

As the series went on, Gollum's look improved along with the technology used to create him. By the time The Hobbit was released in 2012, motion capture technology had come a long way. Programs were used that could simulate the way muscles move over bones and under the skin to create a perfectly realistic creature (via Youtube).

Balrog (The Lord The Rings)

Gandalf and Balrog in Lord of the Rings

In The Lord of the Rings books, a Balrog is an evil being of flame and shadow, about the size and shape of a man. They are Maiar (what Gandalf is) that have turned to darkness. However, when Peter Jackson started adapting the book into films, he made it clear (via Inverse) that he wanted the beast to appear as terrifying as possible and he certainly got his wish.

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The scene where Gandalf faces off against a Balrog is one of the most iconic and quoteworthy of the series. The beasts flaming horns and rings, as well as its fearsome whip, were expertly constructed using CGI, creating an impressive monster, especially for the time.

N.T.I.s (The Abyss)

The NTI creating a water version of the humans in The Abyss

The Abyss is a 1989 film that follows a submarine crew that attempts to explore depths previously unimagined. They end up finding an ancient civilization of advanced beings, known as Non-terrestrial intelligence, or N.T.I.

These creatures attempt to use their abilities of water manipulation to communicate with the humans on the craft. In one scene, a stream of water floats around the submarine and imitates the face of a crew member. It smiles and imitates talking, making its best effort to make contact with the humans. While the N.T.I.s themselves are later represented with animatronics, the scene with the water is fully CGI, a very impressive feat for 1989.

Imhotep (The Mummy)

Imhotep resurrecting in The Mummy 1999

The Mummy is a 1999 film that has become a sort of a guilty please for audiences. It has action, adventure, romance, and mummies, everything viewers could hope for. The mummy in question was named Imhotep, and while he starts the film as a decaying corpse, he slowly reanimates as the film goes on.

Unsurprising for the year it was released, The Mummy's creatures look like CGI, but even to today's viewers, Imhotep looks pretty impressive, even if he isn't convincingly real. In every step of his transformation, he was terrifying to audiences. A few special scenes will stand out to fans, such as the mummy screaming with a largely dislocated jaw, and of course, taking over a sand storm to capture his enemies.

Rango (Rango)

Rango is an animated movie that follows a pet chameleon, voiced by Johnny Depp, that finds himself trying to survive out in the wild. Through a series of events, he ends up as the sheriff of an animal inhabited, western community called Dirt.

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This film is entirely animated using CGI and was released in 2011. Rango is chaotic and strange, but the detailed animation has made it something of a masterpiece. Each animal is given superb texture, with every scale visible on Rango's skin, and every hair, feather, and flea meticulously created to ensure this movie became an unlikely favorite.

Caesar (Rise Of The Planet Of The Apes)

Disney+Rise of The Planet Of The Apes

Rise of the Planet of the Apes is a 2011 film about a scientist named Will Rodman (James Franco), who hopes to invent a drug to cure Alzheimer's disease. He uses an infant chimpanzee, named Caesar, to experiment on, who quickly begins to develop advanced intelligence.

This movie is a prequel to the Planet of the Apes movies from the '60s and '70s (an example of prequel movies that improved their originators), but this time with CGI animals. This allowed Caesar to have realistic movement and texture while having a uniquely human appearance in his eyes and facial expressions. The result is an uncanny animal that audiences can both love and fear.

The Na'vi (Avatar)

Jake Sully And Neytiri In Avatar

Avatar is James Cameron's award-winning masterpiece that was released in 2009. It is set in the future, when humans have begun to travel to a distant planet known as Pandora, home of the humanoid race of beings called Na'vi.

This film was revolutionary for CGI, introducing the motion capture technology that would be used to create countless other breathtaking projects. The Na'vi are very different from humans, making prosthetic makeup or other types of special effects impossible. So instead, over 60% of this live-action film was done with CGI. Behind the scenes footage of Cameron's film will show the actors decked out in equipment meant to capture their every motion so it can be perfectly replicated to fit the beautiful CGI Na'vi.

Aslan (The Chronicles Of Narnia)

Past film adaptations for C.S. Lewis's The Chronicles of Narnia used puppets or animatronics to recreate the lion, Aslan, but that was not an option for the 2005 version. Instead, they used cutting-edge CGI to create a lion that was way ahead of its time.

The movie follows a group of four children that find themselves in a magical world called Narnia. The movie was beautiful and received several awards but nothing looked quite as good as Aslan himself, who, for a majority of filming, was played by an actor carrying a large stuffed lion head. In post, however, a gorgeous and fearsomely convincing lion took his place.

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