Some of the best video games ever made have sequels and prequels, forming a broad chain of games in the same universe you can enjoy. However, just as there are game series, there are also one-off games that stand alone without sequels or prequels.

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Some of these stand-alone games are really fun and might have you wanting more of the same, but since there's just one, you're left unsatisfied. There are quite a few stand-alone games that don't belong in the same universe or even to the same company that complement each other well and could work when played in succession as an unofficial series.

8 Titanfall 2 And Vanquish

Titanfall 2 and Vanquish are stand-alone games with no prequels or sequels, which can leave you dissatisfied. But both games share so many similarities that you would be forgiven for thinking they were set in the same universe.

Both games see you don futuristic mechanical suits to defeat your foes using some heavily advanced firearms. Both games are filled with high-octane action and are set in a futuristic timeline that sees a soldier leave his home to go off-world and face his foes. These similarities make it easy for you to imagine that both games occur in the same universe. If you ever finish one, you can find more of the same or something close to it in the other.

7 Stray And Endling

Stray and Endling both see you assume the role of a cat and a fox, respectively. You must chart a course for yourself through a desolate environment to reach your end goal, all while surviving obstacles and solving puzzles.

While both games aren't so similar in the story and what must be accomplished, they still share a lot of elements and would work well together. You could play through Stray, and if you need more of a similar concept, you could try Endling.

6 Prey And The Callisto Protocol

Prey and The Callisto Protocol take place in a close-quarters environment off-world that sees the main characters battle it out with monstrous-looking adversaries with the threat of the destruction of all life should they fail.

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These games closely resemble each other in more ways than one and heavily feature horror elements, action, and heavy amounts of gore. Both games complement each other well and look great when played in succession.

5 Sifu, Sleeping Dogs, And 9 Monkeys Of Shaolin

Sifu, Sleeping Dogs, and 9 Monkeys all feature well-choreographed combat and action and are all set in China. That's about as much as they have in common, but as they are all stand-alone games that rely heavily on their combat mechanics for the most part, you can see why they would work together.

They all have outstanding story elements about them. All three are more profound than just games set in China with great combat, but that's what connects them and makes them work so well as an unofficial Kung-Fu game trilogy.

4 Dark And Vampyr

If you love gaming and vampires and feel like there need to be more vampire games, you will be glad to find this unofficial vampire game duo that works quite well together.

Both games have unique elements, stories, and lore, but they do have one thing in common, the most crucial thing: vampires. Both games see you assume the role of one of these insatiable creatures of the night, and you must rely on your skill, intelligence, and, of course, vampiric powers to accomplish your goals.

3 Quantum Break And Life Is Strange

In these games, you will find yourself in a warped reality that has you scrambling toward your objective while trying to figure out what is happening. But you have an advantage, a unique ability that gives you the edge during your tasks and saves your life countless times; the ability to manipulate time.

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Quantum Break and Life is Strange have you step into the shoes of time-manipulating main characters in a heavily story-driven game. Although the genres and looks of the games are vastly different, it's not difficult to picture them both happening in the same universe or at least parallel universes with some similarities.

2 Deathloop, 12 Minutes, And Outer Wilds

Have you ever had that feeling of deja vu? Like you've been in a similar situation before but can only vaguely remember? These three games will give you that same feeling but in a fun way.

Deathloop, 12 Minutes, and Outer Wilds all feature characters stuck repeating a particular set of events. At the same time, you try to learn more information from each repeat to piece together the whole plot and break the loop. All three games are excellent on their own and could do with sequels. It's nice to line them up however you want and have a solid playing experience with this unofficial time loop trilogy.

1 Bloodborne And Demon's Souls

These games bear striking resemblances to each other in story, concept, and end goal. In each of these games, you must make your way through a hostile and poisoned land, coming up against and defeating various foes resulting from the poison that plagues the land. Your ultimate goal is to find and destroy this evil's source.

One could be forgiven for thinking this story takes place in the same universe at different timelines with a recurring evil that changes its form and returns stronger every few hundred years. That's not the case, but there's no reason why you can't make it the case during your playthrough. If you play each game chronologically, it lines up almost perfectly as a duo of games where you must quell the same evil that returns stronger each time.

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