Some of the greatest video game franchises of all time started out as individual titles with no plans for expansion or further projects. The Portal series, for example, received its second entry only after the massive success of the first Portal game, and the Super Monkey Ball franchise was only meant to be played in arcades before its console port and sequels.

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Sequels can be risky for developers – fans expect them to surpass the original but also function as a continuation of that world. Sometimes, even the most highly anticipated sequels to the most well-known franchises stop development for any number of reasons.

8 Among Us 2

Among Us was out for nearly a year before it gained popularity thanks to content creators across the internet. It's a simple enough game to scale up to mass audiences, but the developer InnerSloth said that the game's loose code warranted a sequel.

Among Us 2 was announced in late 2020 and then canceled only a month later, as the development team didn't expect the original game to become a household name. Instead of making a whole new game, they focused their attention on improving old code and creating DLCs for their sudden hit.

7 The Legend of Zelda: Mystical Seed of Courage

The Legend of Zelda: Mystical Seed of Courage was meant to be a sequel to Oracle of Seasons and Oracle of Time for the Gameboy Color. It was in development at the same time and would have been released just a few months after the two Oracle games.

The game was canceled early into the development of the trilogy when the team decided to focus on two games instead of three. It was difficult to connect the three games' story together, and many of the assets and ideas that would have been in Mystical Seed Of Courage are instead present in Oracle of Seasons and Oracle of Time.

6 Rainbow Six: Patriots

Rainbow Six: Patriots was planned to be a little different from previous entries in the Rainbow Six franchise. It would have featured quick-time events, interactive cutscenes, and would have been played at a much slower pace than its predecessors.

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The game was canceled for two reasons: it was nearing the end of the Xbox 360's lifetime and the fact that the game wasn't true to the Rainbow Six series. The game was canceled and many of its concepts and assets were re-used in the wildly successful Rainbow Six: Siege.

5 Earthbound 64

Earthbound 64 (also known as Mother 3 at the time) would have been the sequel to Mother and Mother 2 on the Nintendo 64. The game started development soon after the release of the former two titles, but there were several factors that halted its release.

The team was used to developing 2D games, and the 3D space was still a completely new world to many at the time. Additionally, the story suffered multiple changes over the game's development, and eventually, the team deemed Earthbound 64 too complex for the Nintendo 64's capabilities.

4 Star Wars: Knights Of The Old Republic 3

Star Wars: Knights of the Old Republic and the sequel are regarded by many as the best Star Wars games ever made. Although the gameplay is a little dated by today's standards, the immersive worlds hooked players for two incredibly successful games.

The third entry in the series was progressing smoothly until LucasArts had a difficult financial period. The project was canceled, but there are rumors that a third entry in the series is once again under development at the newly-reformed LucasFilm Games.

3 Silent Hills

Silent Hills is perhaps one of the most infamous video game sequel cancellations of all time. The Silent Hill franchise was a smash horror hit that even got its own movie. Hideo Kojima and Guillermo Del Toro headed the project until its cancellation in 2015.

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After the release of Metal Gear Solid V: The Phantom Pain, Kojima and a number of upper development staff left Konami following several disputes. While they went on to found Kojima Productions, who released Death Stranding in 2020, Silent Hills was canceled in the wake of their departure.

2 Project Titan

World of Warcraft has been the king and grandaddy of the MMO genre for what feels like decades – perhaps that's because it is nearly two decades old. For years, Blizzard teased the possibility of a completely new IP that would have been a "next-gen MMO" with the codename Project Titan.

The project was canceled in favor of focusing on World of Warcraft, which was about to enter its peak playerbase, and because Project Titan was too ambitious. The development team lost sight of the scope of the project, and Titan was ultimately canned.

1 Half-Life 2: Episode 3

Forget Half-Life 3, players who played the two DLCs for Half-Life 2 still have unfinished business. The ending of Half-Life 2: Episode 2 was one of the biggest cliffhangers ever in a video game – and it was absolutely ripe for a sequel. Unfortunately, even though Episode 3 was planned, it was never released.

The reasons for this are numerous and enigmatic, but according to Valve, it was due to the scope of the project, the lack of creative drive among the team, and many developers' desire to move away from the original Source engine. The new Source engine debuted with Half-Life: Alyx for VR, perhaps opening the door to a true finale in Gordon Freeman's story.

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