20. Spider-Man 2
GTA's open-world formula shook the industry to its core, but it was Spider-Man 2's movie tie-in back in 2004 that proved to be both a total lightbulb moment for developers Treyarch, alongside turning into the perfect recipe for embodying the web-head for fans. Putting you behind one of the most responsive and experimentally fun control schemes and physics systems seen in an Spidey title so far, the premise was simple; complete a string of movie-influenced missions and thwart Doc Ock, all in a fully-explorable New York City complete with random civilians to rescue, iconic locations to clamber up and scores of thugs to batter into submission. Getting to the very top of the Empire State Building was one thing, but it was having the realisation (after checking out a handful of helicopter patrol patterns overseas) that you could actually get to Ellis Island - and therefore the Statue of Liberty - if you just timed your swings correctly that really the city stand out. This, along with the use of Spidey-sense to hone in on random crimes such as stopping bank heists, catching fallen building workers or snagging childrens' balloons out the sky all combined to give fans one of the most comprehensive wall-crawling experiences of all time.