Not all games are destined to get sequels — not even games that were made with sequels in mind. That means gamers can be left with unfinished stories that leave major plot points unresolved. There are many reasons this can happen. Maybe the game didn’t sell well enough. Maybe its developer became more interested in other projects. Whatever the reason, the games below are some of the most frustrating, because they end on cliffhangers that may never be resolved.

Because we’ll be discussing the endings of video games, proceed with caution if you want to avoid spoilers. Also, be careful about watching the videos, which show the ending of each game.

1. Half-Life 2: Episode Two

You can’t talk about video game cliffhangers without mentioning the most famous missing sequel of all time: Half-Life 3. If you haven’t played the other Half-Life games, you might be wondering what the big deal is. First off, it’s a terrific series of shooters that tells a great story. In fact, the series really laid the groundwork for all story-based shooters to come.

But the worst part is that the last installment, 2007’s Half-Life 2: Episode Two, ended on a major cliffhanger, with the father of one of the main characters being killed when a creature jams a gross tentacle into his brain. Danger looms more than ever when the credits roll, but instead of giving the game a sequel, Valve shifted its efforts to the (also excellent) Portal series. By now the demand for Half-Life 3 has reached such a fever pitch that even if Valve does eventually deliver the game, it couldn’t possibly live up to expectations. Unless maybe it’s a VR game?

2. XIII

This game puts you in the shoes of an amnesiac who wakes up to discover that he may have just assassinated the president — you know, just your usual everyday sort of problem. Obviously it’s your job to figure out who you are, and who might have killed POTUS on the off chance that it wasn’t you. There’s just one little problem: The game ends right when you’re about to learn the identity of the actual killer.

It seems clear that a sequel was intended, but seeing as XIII came out in 2003, you probably shouldn’t hold your breath. Thankfully, the game is loosely based on a comic book, so you can read that if you want closure.

3. Beyond Good & Evil

Many agree that Beyond Good & Evil is a fantastic game and a classic of the PlayStation 2 era. Unfortunately, not enough people played it for Ubisoft to rush out a sequel.

The game stars Jade, a journalist who’s working on a case about a planet-wide alien conspiracy that involves abducted civilians and a corrupt military dictatorship. Jade can kick serious butt when the situation dictates, but she’s also known to compete in hovercraft races and photograph the fauna when she has a free moment. In the game she defeats the imminent alien threat, and then discovers an incredibly powerful new ability that will definitely be useful in the future … if only there was a future.

The game was intended to be the first installment of a trilogy, but poor sales put a wrench in those gears. What was this new power of Jade’s? How might she use it in her continuing fight against the aliens? Despite the 2008 announcement of a sequel that has never materialized, we may never know.

4. Conduit 2

The Wii wasn’t exactly known for its shooters, but it had a few pretty great ones that let you use the Wii remote as a firearm. That’s what the Conduit series did. In these games, the world is under attack by aliens, and various conspiracies and plot twists sweeten the pot as you progress through environments like Washington D.C., Siberia, and an alien space ship.

The end of Conduit 2 comes after you defeat the big bad villain, but are unable to prevent a whole new alien army from heading toward Earth. Things don’t look good for the hero until a portal opens up and out come none other than George Washington and Abraham Lincoln, both of whom are suited up like futuristic soldiers.

“What the… you’re…” says the hero, unable to find the words to vocalize his surprise.

In the gravelly voice of a cigar-chomping soldier, Lincoln replies, “Here to help.”

It’s the perfect setup for Conduit 3. Unfortunately for lovers of American history and/or all things ridiculous, the game didn’t sell enough to warrant a sequel. Bummer.

5. Mega Man Legends 2

Many fans of early Mega Man games might be surprised to learn that he starred in two story-driven action RPGs for the original PlayStation. In the second one, all of the characters are looking for an amazing treasure called the Mother Lode.

After many hours of searching and defeating enemies, Mega Man and his friends find themselves stuck in the world of Elysium, cut off from their home on Terra. After the credits roll, the camera cuts back to Terra, where Mega Man’s buddies are arguing about how to get a rescue mission up to Elysium. And that’s all there is! The camera pans up to Elysium far off in the sky, and it’s over.

While there had been some talk of a Mega Man Legends 3, all hope was lost when Capcom officially cancelled the game in 2011. And now that series creator Keiji Inafune has left Capcom, there’s little hope left that the dangling thread will ever be tied up.

6. Advent Rising

Advent Rising is a 2005 shooter for Xbox and PC that was written by Orson Scott Card. As you might expect with a script by the author of Ender’s Game, Advent Rising takes its sci-fi setting seriously. It’s set in the distant future, when humans and aliens have formed a galactic council to solve disputes.

We all know that kind of harmony can’t last long in a sci-fi story, so soon a group of bellicose aliens called The Seekers decide to wipe humanity out of the universe. After much fighting, our hero learns that he has some latent mystical powers, which he uses to destroy the primary villain. At the same time, a portal opens and sucks him through to a frigid planet, where a strange figure approaches and says, “Come with me, human. There is much to be done.” The words “To be continued” flash onscreen, and that’s the game.

That’s also the series, because Advent Rising didn’t sell well enough to get a sequel. I guess we’ll never know what else there was to be done.

7. Dante’s Inferno

This action game has you play as Dante, a crusader who does some seriously bad stuff while he’s away at war. You return home to find the love of your life not only dead, but her spirit yanked into the ground by Lucifer himself. As luck would have it, a chasm opens up, giving Dante access to the Nine Circles of Hell.

Circle by circle, you make your way into the fiery depths, where you fight and defeat Lucifer, only to learn that he’s tricked you into freeing him from the chains that bind him in Hell. Now that he’s free, Lucifer promises to go up to Heaven and take God’s place on the throne. But before he can do that, you defeat him again and lock him in ice, where he will remain for eternity.

Or will he? In the epilogue, Dante rises to Purgatory, where he pulls a tapestry from his chest, and the camera pans over to it on the ground. The tapestry turns into a snake that slithers away, with Lucifer’s dark laugh echoing in the background. Once again, players are treated to a “To be continued” message that will probably never come true.

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