The possibility of life on other planets has always fascinated humankind. Writers, artists and movie makers have conceived of different types of aliens to fill in the void in the actual knowledge. Developers of online slots are not far behind. There are many alien themed slot machines at online casinos. This article reviews some of them.

Playtech has developed an online slot game titled Alien Hunter that features four aliens, one of which is the wild symbol. The hunter spaceship triggers up to 25 free spins. The alien egg symbol triggers the bonus game. Players collect eggs to multiply the payouts. If they find the super egg then all subsequent wins are doubled. However, one of the eggs contains an evil alien who aborts the bonus game. The alien hunter symbol triggers another bonus game. Players have 15 seconds to catch up to six aliens. They must go after the red aliens that are worth the most. These are followed by the blue aliens and then the green ones. Players who want to avoid the interactive feature can try the software controlled game that awards random prizes. Alien Hunter also incorporates the Playtech Dollar Ball Game. It can be played at all Playtech online casinos like Bet365 and Paddy Power.

Microgaming has an alien themed slot game Planet Exotica in its Sneak a Peek series. There are five sexy alien strippers who perform at an intergalactic night club Planet Exotica. The other thematic symbols are the bouncer, bartender and valet. The Planet Exotica logo is the wild symbol and the smooch is the scatter symbol. Planet Exotica offers some sensual animations in the win combinations. In the Select A Smooch bonus the player is initially awarded up to 10 free spins with an up to a 2x multiplier. Both the number of free spins and the multiplier can be enhanced while the bonus game is played out. In the Sneak A Peek bonus one the strippers appears on the platform. She sheds the garments selected by the player through a tile match process. The player gets bonus points for each garment removed. Planet Exotica can be played at Microgaming online casinos like Spin Palace, Platinum Play and All Slots.

Area 21 is an alien themed slot game from the software provider Cryptologic. The title is taken in part from Area 51, a location that has reported a large number of UFO sightings. The slot game has a futuristic look with a number of well dressed alien symbols. The animations are pretty nifty as well. The wild symbol resembles some kind of spaceship and awards the highest lime payouts. Area 21 is the scatter symbol. It awards scatter payouts and also triggers the bonus game on the second screen. The significance of the ‘21’ is apparent from the bonus game because the player plays a hand of black jack to determine the free spin parameters. The hand is played according to the usual blackjack rules. In the least the player will get 10 free spins at doubled payouts even if he loses the hand. If the player is dealt a natural blackjack he gets 25 free spins with payouts multiplied 5 times. There are several intermediate awards based on the player splitting or doubling down. Area 21 can be played at all Cryptologic online casinos like InterCasino.