Alien Slot Machines Online: Ready to Stop the Invasion?

The best alien slots online combine the creativity of sci-fi with the excitement of modern slot games. In addition to showcasing fascinating creatures from other planets, these slot machines are also loaded with great bonus features and offer an excellent experience.

I highlight my favorite alien slot games available online below. Before I dive into their features and gameplay mechanics, here’s a quick overview.

Best Aline Slots Online (Overview)

UFO Pyramids

UFO Pyramids combines alien and Egyptian themes into one unique slot game. This very high volatility game was developed by BGaming and has an RTP of 97.17%. It uses a pyramid-shaped grid equipped with a pays anywhere system.

This alien-themed slot uses a cascading wins feature. Winning symbols are removed and replaced after each winning spin, allowing new symbols to land on the board and create new paying combos.

Winning in UFO Pyramids starts in the base game with the random multiplier feature. You can trigger up to 500x win multipliers that pay anywhere they appear on the grid. There is also a free spins round, triggered by three or more scatters, that uses a cumulative multiplier feature. The free spins bonus game takes place on the aliens’ home planet. 

Impatient or unlucky players do not need to wait for three scatters to appear to activate the free spins mode. You can use the buy feature to trigger the mini game at any time. However, it is worth noting that the buy feature costs 100x your stake, so use it sparingly.

Red Dog Casino has real money and free versions of UFO Pyramids. If you create a new account, you can use the $8,000 deposit match bonus to expand your bankroll before playing this alien slot game.

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Farmageddon

DiceLab’s Farmageddon offers a maximum win of 10,000x and an RTP of 96.57%. In this farming-themed alien slot game, you can take advantage of free spins and multipliers to help you win one of the game’s four jackpots.

The Angry Farmer defending his animals from the invaders serves as the wild symbol. There are also milking machines that act as multipliers, offering up to 3x prizes. The Cow Bell symbols offer instant prizes.

Scatter symbols can trigger the free spins mode in Farmageddon. Once activated, your multipliers will begin stacking to help you rack up bigger wins during the feature.

The UFO symbol, which only appears on the last reel, can collect and award other bonus symbols, including jackpots. The game’s four jackpots include:

• Mini jackpot = 20x stake amount
• Minor jackpot = 50x stake amount
• Major jackpot = 100x stake amount
• Grand jackpot = 500x stake amount

You can use the Power Bet option to increase your odds of activating free spins by increasing your stake by 50%. Or try the Buy Feature to pay to trigger free spins automatically.

Bovada is the best casino for trying your luck at Farmageddon. It offers both free and real money versions of the game. Also, you can get up to $3,750 in extra funds with the casino’s crypto welcome deposit match offer.

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Back to Venus

It Came From Venus by Betsoft was a popular alien slot game in the mid-2010s. Back to Venus, the sequel, offers the same excitement as the original, with a higher RTP. The original game had an RTP of 95.80%, and the sequel has a return of 97.07%.

An increased RTP is not the only advantage the sequel has over the original. The hit rate, for example, has also been increased from a below-average 10.08% to an above-average 45.28%.

Back to Venus has plenty of bonus features, too, including sticky wilds that stay on the reels for two additional spins. There is a free spins mode as well that you can activate with the rocket bonus symbol. Losing spins can quickly become profitable, too, if you randomly trigger a respin with the stick and respin feature.

If you want to try the Back to Venus slot game today, then you should sign up for an account at Ignition Casino. It offers a free demo and an exciting paid version of the slot. New members can get up to $1,500 in bonus casino funds with the crypto welcome bonus.

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Vegas Space Heist

Vegas Space Heist combines alien life forms with the glitz and glamour of Sin City. The slot was released by Qora Games in 2025, making it one of the newest alien slots on my list. It has an RTP of 96.09% and uses 720 pay ways.

You need at least three matching symbols on adjacent lines to earn a payout in this 3-4-5-4-3 slot. Also, wins are awarded from both left-to-right and right-to-left.

There is a wild alien symbol that appears on the middle three reels in Vegas Space Heist. It replaces every symbol except the Money bonus symbol. Also, combinations that use wilds are guaranteed to reward you with the highest possible payout.

Vegas Space Heist also uses special coin symbols that you can collect during the base game. Any UFO that collects a coin symbol has a chance to trigger the Jackpot Radar mini game. During the bonus round, you can win one of five fixed jackpots, including a grand prize worth 1,000x your stake amount. 

SlotsandCasino is the best site for playing Vegas Space Heist for free today. It offers a free-to-play demo, as well as a real money version of this alien slot. Every new member who makes a qualifying deposit can claim a crypto welcome match of 500% worth up to $2,500.

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Nebula Jackpot

Nebula Jackpot from DiceLab also uses 4096 pay ways instead of pay lines. It pays left-to-right, and you need at least three matching symbols on adjacent paylines to create a winning combo. The game has an RTP of 96.00% and uses a 6×4 grid.

The galaxy symbol acts as a wild in Nebula Jackpot, substituting for every symbol other than the scatter. Speaking of the scatter, this bonus symbol can trigger up to 100 free spins. 

You need at least three scatters to trigger the bonus feature, and the more scatters that trigger free spins, the more spins you will get. Any scatters that appear during free spins will add more spins to your remaining total. Nebula Jackpot does not put a limit on the number of free spins you can trigger during the feature.

Wilds are upgraded during free spins, too. Any wilds that appear on reels two through six can have up to a 3x multiplier. If multiple wilds appear on the same line, their multipliers are added together to create even bigger wins.

You can experience all the fun of Nebula Jackpots for free today at El Royale Casino. The casino also offers a paid version of this exciting alien-themed slot machine. New members who qualify for the VIP welcome bonus can get up to $23,000 in extra slot funds.

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