With the help of companies such as Trixter, Industrial Light & Magic, and Method Studios, Marvel has given fans a flurry of breath-taking visual effects moments over the years. It is said that the best CGI moments are those that you don't even know are CGI which has secretly been the case a few times in the MCU.

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VFX is a very complicated art form and hats should be tipped to those who are able to create stunning visuals to the level of the MCU, but there are always moments when bad CGI stands out like a sore thumb and poor VFX can take you out of the story. With that being said, here are five of Marvel's best and worst CGI moments.

Best: Iron Man Mk 2.

mk 2

Way back in 2008 Robert Downey Jr. first suited up as Iron Man and created the original suit in a cave "with a bunch of scraps!". However, the focus here is on the second generation armor he dawned later on in the movie.

Fans first saw the suit in a plain silver before it was colorized with gold and "hot-rod red". Regardless of the color, Tony Stark suiting up in the Mk. 2 for the first time was a fantastic VFX moment that, with the lighting and textures it had, could convince anyone that the suit was real and functioning.

Worst: Iron Man Mk. 45

mk45

At the opposite end of the scale, Tony Stark debuted his Mk. 45 armor in Avengers: Age Of Ultron when he arrived on Sokovia to defeat Ultron. The overall texture of the suit was 'shinier' than the others which may have contributed to its more obvious VFX generated look.

The earlier films set a very high bar for the realism of the Iron Man suits so perhaps without that comparison, the Mk. 45's CGI look would be less noticeable.

Best: Young Tony Stark

young tony

In Captain America: Civil War, Tony Stark first appears when he is giving a speech to MIT while demonstrating his B.A.R.F technology used to re-create and deal with traumatic memories. Tony's memory was of the last time he spoke to his parents alive when he was a teenager.

This scene was shot on the last day of filming as RDJ had to shave his beard to play the younger version. RDJ played the younger version and was made younger using the latest age-reversion technology. Take a second to think about how amazing it is to make an actor look like he did in his teenage years, even if it's not 100% visually perfect, it was undoubtedly impressive.

Worst: Bruce Banner In The Hulkbuster

Mark Ruffalo in Avengers: Infinity War

In Avengers: Infinity War Bruce Banner and Hulk were certainly going through a rough patch which meant Bruce had to find another way to fight in the battle of Wakanda. The conclusion was to have him inside a new version of the Hulkbuster armor fans saw in Avengers: Age of Ultron.

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The suit looked perfect in the final battle except for the moment just after Thor arrived and the Hulkbuster helmet retracted to reveal Bruce Banner. Unfortunately, It was a case of 'floating head syndrome' for Bruce in the Hulkbuster.

Best: Fake RDJ

fakerdj

In Iron Man 3 RDJ, unfortunately, suffered an injury on set which prevented him from filming for a short while. As you all know movies are run on schedules and sometimes, these schedules cannot be altered.

As a result, Marvel managed to the best use of CGI.

Worst: Black Panther Vs. Killmonger

T'Challa fights Killmonger in Black Panther

One of the main talking points in the conversation of Marvel's CGI moments is the final fight in Black Panther between T'Challa and Killmonger in the underground Vibranium cave in Wakanda. Although the fight certainly had its moments, the computer-generated nature of the fight did shine through.

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That being said, the nature of Black Panther's fighting style is very fantastical and acrobat-like and would be incredibly hard to choreograph to the same standard with live-action actors.

Best: Thanos

Thanos

Thanos was played by Guardians of The Galaxy onwards. Practical effects were used for Damion Poitier's appearance but then Marvel transitioned to CGI for Josh Brolan.

Even though the appearance of Thanos himself changed slightly from Guardians to Avengers: Infinity War, the end result was incredibly detailed and lifelike with Thanos even having stubble on his face if you looked close enough.

Worst: Iron Man Suit In Civil War

civil war

Another case of floating head syndrome happened in Captain America: Civil War when Tony Stark first speaks to Spider-Man in the airport battle without his helmet. This sequence utilized green screens as it was a very complicated fight to shoot but sadly, in the image above, the lighting on Tony Stark's head compared to his suit made the difference between what was real and what was CGI more noticeable.

In the older Marvel movies, such as Iron Man 3, RDJ was inside the completed top half of an Iron Man suit, whereas in the later movies, Marvel seemed to use an incomplete version of the top half of the relative armor that was then replaced and filled in with CGI.

Best: Doctor Strange Battle

Doctor Strange - Twisted New York

Inception with its city-bending VFX. In the final battle with Kaecillius in New York, fans saw Doctor Strange running up rippling buildings and along with self-assembling platforms while the streets folded into each other.

Marvel worked with four VFX studios for this movie, and while they helped to show us that Doctor Strange was a master of the mystic arts, ILM, Framestore, Luma, & Method studios all showed us that they were masters of the visual.

Worst: Spider-Man Suit In Civil War

Spider-Man Civil War

Captain America: Civil War saw the debut of Tom Holland's Spider-Man in a new suit designed by Tony Stark. It was certainly the moment fans had been waiting to see ever since the Marvel-Sony deal was announced.

The only quip fans seemed to have with his appearance was the VFX-heavy look of the suit in the airport battle.  The nature of the suit seemed to be skin-tight, comparable to Lycra which meant that when Spider-Man moved his arms there were no folds or creases in the fabric. Perhaps this was intentional and is part of the design of the suit, but it contributed to the noticeability of the CGI.

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