I remember the first time Thanos was introduced to us. It was in a short that aired after the credits for 2012's Avengers.

I didn't know who he was, but the gasps from the audience said everything: guys, it is so on.

Now, six years and many teasers later, it actually is on. Thanos is the star bad dude in Avengers: Infinity War, which will hit theaters worldwide April 27. It looks to be the most epic, and successful, installment yet in the Marvel Cinematic Universe (MCU).

Oh, how things can change in six years. In that time, the MCU has expanded exponentially. Which makes the third Avengers movie intimidating.

To pump myself up for Infinity War, I watched the Thanos teasers that have been shown post-credits since The Avengers. I was reminded in one that Nebula, also known as Thanos' adopted daughter, also known as "the blue chick from Guardians of the Galaxy," was a villain in the first Guardians movie. This was jarring. Infinity War may as well be called "every hero ever vs. Thanos." And she's in it, so I just lumped her in with the good guys.

A quick Wikipedia search for Guardians of the Galaxy Vol. 2 explains that Nebula was also a villain in that movie, but eventually reconciles with her sister, Gamora (also known as "the green chick"), and I guess that makes her a full-fledged hero. But I'm still not completely sure. It was a confusing time.

This is an enduring problem with MCU films for me, especially as they increasingly become ensemble deals. Every time a new one comes out, there are always whispers from the cinema audience (and myself). "Who is that again? Where is she from? Didn't he die?"

Back in my day, the Avengers were comprised of Iron Man, The Hulk, Thor and Captain "Not a Real Hero" America. (Black Widow and Hawkeye were technically Avengers too, but they didn't have their own feature films so they only half counted.)

Not anymore. Look at this. Who are all these people?

Enlarge Image Marvel Studios

OK, I'm kidding. I know who all these people are: Eyepatch Thor. Captain "Trying to make up for my lack of superpowers with a beard" America. Blonde Black Widow. The Guardians of the Galaxy Gang. Black Panther & Co. Don Cheadle. And so on.

Don't let the cynicism confuse you, I am very excited. I would pay $20 just to watch two hours of Teen Groot. Every time I see one of the hundreds of Infinity War posters plastered around Sydney I think, "man I can't wait to see that."

But walking to work this week, I saw a billboard with all of the film's characters sprawled across it. I was overcome with a sense of dread. It was like high school all over again.

"I haven't studied hard enough for this."

To get the most out of Infinity War, the culmination of 10 years and billions of dollars in Marvel films, it would be best to be up-to-date with all 23 characters on the poster. This seems like an unfair ask.

I've seen every film in the MCU, but with the exception of a few, I've only seen them once, usually upon release. That means I've spent around 36 hours of my life watching Marvel films. That's more time than I spent studying for any high school or college exam, and yet I feel less prepared than ever.

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Back in yonder year, when a new Lord of the Rings film would be released, my family and I would watch the preceding film(s) the night before to catch up on the the Fellowship. But Infinity War is the 19th movie in the MCU! Ain't nobody got time for that. Not even Stan Lee got time for that.

I've purposefully avoided using the word "complicated" here. The MCU isn't confusing or convoluted, there's just a lot of it. The baseline of knowledge is also low. No movie is ruined by your not having memorised each character's history, family tree and dietary requirements. After all, charming superhero takes on new threat in a spectacular showdown is a formula that these days only DC seems capable of wrecking.

I'm not saying the films should be dumbed down for amnesiacs like me. Just that less can be more, and that Marvel's expanded universe would almost certainly be better off with a little contraction.

I saw the first Guardians of the Galaxy three times, and also liked the second one, but I was still hazy on Nebula's character arc. These are the types of details that get lost in the shuffle over the course of a decade and 19 films. I'm sure there are a lot of people out there who have every character profile memorised, but I'm also sure there are more people out there who don't.

The first Avengers felt special because it was four heroes (plus two half-Avengers) forming a supergroup. It ended with the first appearance of a new supervillain in Thanos. Six years later, The Avengers are still a supergroup, but the individual parts feel less significant.

On the plus side, now that I've done my research for this column I won't have to wonder too much about Nebula's motivations when she pops onscreen in Infinity War.

Only 12 hundred more superheroes to catch up on before the big day.

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