Some games cost very little and flourish in the market. Collectively, their success stems from a variety of factors, but one thing that remains consistent from title to title is that each game's gameplay is incredibly enjoyable. Things like graphics, lasting appeal, and online functionality can also play a big role, however.

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These days, most video games cost tens of millions of dollars to develop, with millions more being spent on marketing and post-release support. That's not to say that all modern games cost a fortune, however. The following titles cost relatively little to develop, yet they were still able to gross millions of dollars in sales.

Updated September 9, 2022, by Tom Bowen: There are a lot of things that can determine whether or not a game will be successful, but while bleeding-edge graphics and big-name voice actors can certainly go a long way, an enjoyable gameplay loop is arguably a lot more important. Those who think otherwise need only take a look at some of the many indie game success stories, which not only serve to highlight this point perfectly but also prove that a big budget isn't always required when it comes to developing a best-selling video game. These low-budget games sold millions of copies and many remain incredibly popular to this day.

15 Flappy Bird

Thanks in large to the questionable monetization tactics that some of them employ, mobile games now account for a significant chunk of modern video game spending, with billions of dollars being spent across the App and Google Play stores each and every month. Flappy Bird was one of the earliest viral success stories in this regard, with its creator at one point raking in more than $50,000 a day through in-app advertising.

This may not seem like much when compared to the likes of Diablo Immortal, but it's important to take the scale of each project into account. Countless people worked on Blizzard's controversial title over the course of several years, including several whose sole purpose was to figure out how best to manipulate players into spending their money. By contrast, Flappy Bird was created by just one man over the course of a few days, making its 50 million+ downloads far more impressive.

14 Five Nights at Freddy's

In June of 2014, Scott Cawthon launched a Kickstarter campaign for a horror game called Five Nights at Freddy's, with the developer seeking a rather modest $10,000 in funding. He ultimately ended up canceling the project before it was fully funded, but this figure should still give players some idea of the kind of budget that went into the development of the first FNaF game.

In the years that have followed, FNaF has gone on to become one of the biggest franchises in gaming. It now spans multiple genres and mediums, with its complicated and ever-expanding lore helping to evoke a near-endless supply of intrigue among players. Cawthon has never revealed just how much he's made through the series, but, at one point, the original game was estimated to be raking in more than $15,000 a day in mobile sales alone.

13 Undertale

Undertale is not only one of the best indie games of the past decade, but one of the best games period. What makes this all the more impressive is the fact that the game was funded almost exclusively through Kickstarter, with a little over $50,000 pledged throughout the course of the campaign. To say that the game exceeded expectations would therefore be a bit of an understatement.

Upon its release, Undertale garnered widespread acclaim, with many critics praising its innovative gameplay mechanics and fantastic sound design. In the years since, it's sold millions of copies, with some reports suggesting that its creator Toby Fox made more than $25m through Steam sales alone. Given that Steam will have taken a cut of the profit and the fact that the game is available on multiple platforms, it seems safe to assume that the true total is higher still.

12 Terraria

The gaming industry often works in cycles, at least when it comes to popular genre trends. These days, battle royales and social deception games are all the rage, but a decade or so ago, people really couldn't get enough of sandbox games with crafting mechanics. Though it may not be the most successful game to fall into that category, Terraria is widely considered to be one of the best.

As of April 2020, Terraria had sold in excess of 14 million units on PC alone. Given the huge number of platforms on which the game is now available, the total number of copies sold really is anybody's guess, though it's definitely above the 20 million mark. For those wondering, that equates to more than $200 million in revenue.

11 Rocket League

Within just two years of its initial release, Rocket League had already sold more than ten million copies. Since then, it's continued to generate millions of dollars of revenue through the sale of microtransactions and has become one of the most popular eSports titles around. Not bad, for a game that's reported to have cost less than $2 million to develop.

Unlike more traditional sports games, Rocket League places players behind the wheel of a turbocharged car and then has them battle it out with bots or other players in what is effectively an over-the-top soccer match. It's now free to play on most platforms, which has played a pivotal role in the game's continued success on both consoles and PC.

10 Outlast

Outlast is a relatively low-budget game, but still made a ton of money. The website of gameindustry.biz details how Outlast cost a mere CAD 1.36 million to develop but has now grossed well over $64 million. All things considered, that's a pretty emphatic return for the game's developer and publisher, Red Barrels.

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The simplistic gameplay of Outlast proved to be very effective as part of a first-person narrative. For game development companies, it is a dream come true. Put little into a game and receive a high return. Its low budget does not correlate with the enjoyability of its gameplay. Outlast is a frightening first-person survival horror game that fans of the genre need to play.

9 Stardew Valley

Many video games cost over $10 million to develop, but games like Stardew Valley prove that it's not always about money spent. With Stardew Valley, simplicity is key. As detailed by gamerevolution.com, "By the end of 2016 it was estimated that Stardew Valley was owned by more than two million Steam users.

This statistic puts the title's estimated revenue at over $25 million on PC alone. Since the game was released on numerous platforms, including iOS, Android, Xbox One, and PS4, Stardew Valley may have grossed nearly $50 million. It has earned so much revenue, and one person developed it.

8 Minecraft

Of course, any list detailing indie success stories wouldn't be complete without Minecraft; one of the highest-grossing video games of all time. The original Minecraft was developed by just one person named Markus 'Notch' Persson and is an anomaly in gaming due to it grossing way more than its development cost.

It's an indie game that has too many sales to count. Estimates by gamespot.com put its sale figures above 176 million. In September 2014, Microsoft purchased Minecraft and developer Mojang for $2.5 billion. This is one low-budget game that made a ton of money.

7 Starbound

Starbound is an indie game that places players on an alien world where they have to repair their ship in order to explore the universe. It's one of the few procedurally generated games that have really paid off for their developers and a must-play for those who enjoy 2D action-adventure games.

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Developer Chucklesfish sourced their cash flow by using crowdfunding. Starbound stayed in the early access phase for a great deal of time, but in the end, it was worth it. According to gamesindustry.biz, Starbound has sold over $2.5 million copies, putting their sales figures in the tens of millions of dollars.

6 Runescape

Runescape is a free-to-play massively multiplayer online role-playing game that gives players the option to become paid members. Comparable to games like the Elder Scrolls Online and World of Warcraft, Runescape has addictingly fun and intuitive gameplay which has helped it to attract a sizable and dedicated fanbase during the many years since it first went live.

According to gamesindustry.biz, Runescape's developer Jagex reported total sales of £50 million ($77 million). The graphics are not the greatest, but it's one of those games where it doesn't matter. Performing tasks like fishing, blacksmithing, mining, and completing quests give Runescape high replay value.

5 Tetris

Developed primarily by Alexey Leonidovich Pajitnov, a Soviet Russian software engineer, Tetris gained widespread popularity when it was released on the Nintendo Game Boy. Since then, it has become the best-selling game of all time, with more than 500 million sales.

This simplistic game tests players' puzzle-solving skills in a fast-paced environment. It's addictive and fun, which is why it has received numerous spinoffs and continues to grow in sales. If each copy of Tetris were priced conservatively at $5 the game would have earned $2.5 billion.

4 Fez

Fez is a puzzle-platform indie video game that was released in 2012 for Xbox Live Arcade. For those who don't remember, Xbox Live Arcade was the arcade store on the Xbox 360. Through this platform, Fez was able to sell around 20,000 copies on its first day.

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Despite having numerous bugs, Fez scored a 90 on Metacritic. Although the game appears to be two-dimensional, it is actually a three-dimensional game since each of the four sides can be rotated. Playing one of four sides in the game works well in practice. Fez has been ported to the PlayStation 4 and other consoles, so it's not too late to play Fez today.

3 Castle Crashers

Games that launch on Xbox Live Arcade often have a low budget. Castle Crashers is a 2D game with a basic premise, yet is addictingly fun. For anybody who likes beat 'em up video games like Super Smash Bros., there's a strong chance they'll like Castle Crashers as well. It supports four-player cooperative gameplay, which is even more reason to play Castle Crashers.

The top-selling Xbox Live Arcade game of all time is Castle Crashers. According to venturebeat.com, it gained over 2.6 million downloads. Due to the wide success of the game, it was ported to consoles like the Nintendo Switch, PlayStation 4, and Xbox One.

2 Dead Cells

As reported by pcgamer.com, Dead Cells has now sold well over a million copies, with most of those being on the PC. Not far behind are the sales from the Nintendo Switch port, with other console versions also contributing a somewhat sizeable amount to the grand total. As time continues to pass and word of the game's excellence spreads further, two million seems very achievable.

This roguelike-Metroidvania has received critical acclaim for its smart combat system and stellar gameplay elements. Players must restart the game when they die, which forces players to learn from their mistakes. Dead Cells could be the best Metroidvania game ever to be released. Even with a relatively low budget, it managed to earn millions of dollars in sales.

1 Hollow Knight

Hollow Knight is another Metroidvania game that started with a low budget and went on to be a huge hit. Inspired by games like Dark Souls and Bloodborne, Hollow Knight has grueling boss fights that may deter some players. Those who aren't afraid of a challenge, however, may find themselves with a new favorite game.

According to gamingbolt.com, Hollow Knight was made "on a minuscule budget, with a positively tiny development team behind it. The game has a low price of approximately $15, which is even more reason to buy Hollow Knight. With all that said, Hollow Knight has sold more than 2.8 million units.

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