As with all licensed properties, video games based on pre-existing IPs don't always last forever, even if they're great. Rights holders move on, rights ownership ends, and sometimes a studio just can't sustain the support a game needs to maintain its availability for an extended period of time.
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This has unfortunately been very widespread too Marvel games. Due to property rights changing hands (in large part because Disney started gobbling them up as the MCU took off), there are plenty of amazing Marvel games that you just can't buy anymore. There may be some used copies on Amazon, but if you're looking for these games in an online store, you're out of luck.
Spider-Man: Web Of Shadows
Its legacy lives on in meme culture
We're going to burn through a few games starring the web-head before branching out into the rest of Marvel, as a surprising number of excellent Spider-Man games were churned out over the past two decades. First out is Spider-Man: Web of Shadowsan excellent open world action game developed by Shaba Games and Treyarch.

Marvel's Spider-Man has proven that it needs a desirable web of shadows feature
A prominent Web of Shadows feature has long been requested for Marvel's Spider-Man and Insomniac may no longer be able to deny it in future entries.
Web of Shadows followed a similar formula to other 2000s open worlds Spider-Man game. You can swing through Manhattan, encountering random events and collecting collectibles. It featured an evolved version of the combat system that allowed you to fight enemies on walls and in the air, as well as the ability to switch between the red and blue and black suits at any time, each with its own moveset and skill tree. Web of Shadows was removed when Activision's Marvel ownership ended, a common theme we'll see a lot in this list. But just last week, Twitter/X user Stormslayer released a fan-made remaster of the game that runs on PC emulation.
Ultimate Spider-Man
Got a posthumous nod in Marvel's Spider-Man 2
Also developed by Treyarch, Ultimate Spider-Man came on the scene a few years earlier Web of Shadows and just 15 months after the motion picture Spider-Man 2. This one came loaded with a cel-shaded art style meant to evoke the look of the comics it was based on, but it had another ace up its sleeve that changed the way people watched Spider-Man game forever.
Not only did it Ultimate Spider-Man allows you to explore the open world as Spider-Man, but you would switch to play as Venom at set times while still having access to the open world. Spidey was faster and more mobile, while Venom, while still able to web swing, was heavier and more powerful. This even got a nod Marvel's Spider-Man 2 during a sequence near the end of Act 2, where you briefly play as Venom and venture into New York. Sadly, Ultimate Spider-Man was also a victim of expiring rights and is no longer available.
Spider-Man: Shattered Dimensions
The best of the non-open world Spider-Man games
Following web of shadows, Treyarch moved on to develop Call of Duty full-time games, and Activision handed over the rights to Spider-Man game over to Beenox, the studio that ported Web of Shadows to PC. Beenox's first crack at a Spidey game was Spider-Man: Shattered Dimensions, a linear action-adventure game featuring not one, not two, but four different versions of Spider-Man: Amazing Spider-Man, Spider-Man Noir, Spider-Man 2099 and Ultimate Spider-Man.

Shattered Dimensions' Spider-Man Noir Never Getting a standalone spin-off is a shame
Spider-Man: Shattered Dimensions takes the crown for the best depiction of Spider-Man Noir and it's a shame that iteration never got its own game.
Featuring an all-star cast of former Spider-Man voice actors, Crushed dimensions sold out his battle and was better for it. There was definitely a sense of limitation due to the lack of an open world, but the story and gameplay were so strong that this was still a must for Spidey fans. It was so good that author Dan Slott used it as inspiration for Spider verse comic plot, which was later adapted into the modern classic animated film Spider-Man: Into the Spider-Verse and its sequels. Sadly, Crushed dimensions (and its minor sequel, Edge of Time) were also victims of Activision's rights termination. The good news is that Stormslayer has also released a fan-made remaster of this game for PC emulators.
Marvel Ultimate Alliance
The King of Beat 'Em Ups
When beat 'em ups were still one of the most popular genres in gaming, Raven Software followed suit X-Men Legends game with Marvel Ultimate Alliancea team-up beat 'em up featuring 23 playable Marvel heroes, anti-heroes and villains, all drawn from across the Marvel Universe. The “Next Generation” versions (PS3 and Xbox 360) featured Colossus and Moon Knight as additional characters, while a pair of expansion packs added eight more characters to the roster.
Although rudimentary in its RPG qualities, with automatic upgrades rather than character building, Marvel Ultimate Alliance It was still fun to play, with each character feeling distinct and boasting unique abilities that could be combined with other characters in a variety of cool ways. Just like every other game on this list (so far), Marvel Ultimate Alliance was delisted after the rights expired at Activision. While Marvel Ultimate Alliance 3: The Black Order for Nintendo Switch tries to recreate some of the magic, it can't quite recreate what made this game so special.
Marvel Ultimate Alliance 2
A worse sequel, but not without its charm
Taking over from Raven Software (after the studio moved on to making first-person shooters and eventually became a Call of Duty team), developed Vicarious Visions Marvel Ultimate Alliance 2, a direct sequel to the first game that ditched the original story and instead followed a plot adapted from Civil war and Secret Wars comic stories. While Vicarious did his best to follow in Raven's footsteps, Ultimate Alliance 2 came out feeling like a smaller version of the first game. However, that doesn't mean it's not worth playing.
With a roster of 34 playable characters (with a controversial Juggernaut pre-order character thrown in), including some currently obscure names like Cable, Sentry and Songbird, Ultimate Alliance 2 still had some really cool fusion moves that two characters could perform at the same time. It was also graphically improved over its predecessor, and the custom storyline allowed for some branching narrative choices depending on which side you chose, resulting in potential boss battles against characters like Iron Man or Captain America. As yet another victim of Activision's rights expires, Marvel Ultimate Alliance 2 can no longer be purchased. Weirdly, there's still an Xbox Store listing for it, just without a buy link.
Deadpool
A relic of the pre-Ryan Reynolds era
Developed by High Moon Studios, the team behind the criminally underrated Darkwatch and the bourne conspiracy, Deadpool was the first attempt to rehabilitate Marvel's Merc with a Mouth after his notoriously despised adaptation in the X-Men Origins: Wolverine. Honestly, it does a pretty good job. Long before Ryan Reynolds had the opportunity to revitalize the character on the big screen, 2013's Deadpool the game captured everything that fans love about the character in video game form.

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Played by Nolan North (aka Nathan Drake), Deadpool is his vulgar, absurd, fourth-wall-breaking self, complete with dual katanas and pistols to slice up enemies, as well as a few other weapons as you progress. The humor and voice acting are pitch-perfect, and while the combat doesn't revolutionize action games, it's still a ton of fun, with plenty of skill upgrades and all the gore and gore you'd expect (and even some stealth options, oddly enough). Deadpool was also a victim of Activision's license expiration, but a spiritual successor, Marvel's Deadpool VR, is available if you have the hardware for it.
Marvel's Avengers
Imperfect Live-Service Elements Sank A Solid Character Action Game
We can finally stop blaming Activision for these games not being available today. Marvel's Avengers was a live-service character action game developed by Crystal Dynamics and published by Square Enix. This was the first crack at a Marvel game for either company, but you wouldn't know it. The story does an admirable job of separating its now iconic characters from their MCU counterparts, delivering a solid narrative of the Avengers “reassembling” after a devastating attack they failed to prevent.
The live service elements are what ultimately dragged this game down. Marvel's Avengers is a decent character action game, hampered by the need to keep all characters balanced for multiplayer to work. The combat itself is actually quite fun (the disappointment of Hulk being captured aside), and each character has a very varied moveset that feels like it could serve as a starting point for a solo game. They all have a variety of awesome unlockable skins as well. The post-release content is also excellent, with Hawkeye Future imperfect the plot is a particular highlight. But in the end, Marvel's Avengers was brought down by trying and failing to maintain a live service formula that didn't fit its ideas or design, leading to the cancellation of further updates. Today, those who originally purchased it can still play the single-player content offline, but the game is no longer available for newcomers to purchase.

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