Commander Keen 2: The Earth Explodes

aka: Commander Keen: "Invasion of the Vorticons" - Episode Two: The Earth Explodes
Moby ID: 217


Commander Keen 2: The Earth Explodes is the second game in the first trilogy of Commander Keen platform games, called Commander Keen: Invasion of the Vorticons.

In this episode a Vorticon Mothership is poised above Earth, preparing to destroy the planet with their deadly Tantalus Rays! Commander Keen's mission is to stop these evil Vorticons from blowing up the Earth. In order to do this you need to find and destroy each X-14 Tantalus Ray, powered by cells from the big purple Space Amoeba.

The game begins with a top-down map of the mothership. This is the level select screen, where you can walk around and choose the next level you want to enter. On each level, you have to find the exit; if this is one of the levels with a Tantalus Ray, you've got to destroy the Ray before exiting. Once you reach the exit, you're back on the map of the mothership.

The levels are typically full of enemy creatures and hazards. If Keen gets shot or touched, or falls into a pit or hazard, he dies, and you're booted out of the level back to the overhead map and lose one life.

Thankfully, Keen can defeat some of the enemies with his raygun. He also has a pogo stick which allows him to jump very high. Other items to find include keycards that open locked doors and bonus items which give score (Keen gets an extra life if he collects enough score).

Groups +


Credits (DOS version)

4 People

Creative Director
Level Design



Average score: 65% (based on 2 ratings)


Average score: 3.6 out of 5 (based on 48 ratings with 6 reviews)

Help Keen destroy the laser cannons that will destroy earth in the second part of the infamous and brilliant series.

The Good
Graphically it's OK and just about the same as part one, which means cute graphics and funny and totally crazy looking enemies. The game continues the story started in the first episode, but has a story of it's own too. Keen has infiltrated the Vortican Mother ship build to destroy earth. He now has to find all the laser cannon's and destroy them to save the famous cities where they are aimed at, such as Moscow, New York and London. You will find these in the different levels spread on the main map similar to part one. Just like the graphics the gameplay is the same because it's basically the second part of the same release. This means you will find smooth gameplay rarely seen on the PC in games of that age. This one is not shareware just as part 3 and unlike part 1 (This system is used in many of Apogee's games). You can still buy this game, however. If you loved the first part you will love this one too, for sure.

The Bad
The gameplay is a bit dated by today's standards. Another problem comes with shooting because you need to use the combination of ALT+CONTROL to shoot. This is especially frustrating if you need to shoot and do a hi-jump with keen's pogo stick since you use CONTROL to jump and ALT for the pogo and combining these two results in a hi-jump which is needed sometimes.

The Bottom Line
Another fun classic platform game that is just the second part of the same release as part one so don't expect anything new. This is not really a problem since part one is also a brilliant classic.

DOS · by Rensch (203) · 2005

Keen's second adventure is even more amazing than the first

The Good
Before id Software released their hit first-person shooter, they created a trilogy of platform games starring Billy Blaze, who transforms into Commander Keen after donning his brother’s helmet. His first adventure took him to Mars where he recovered four vital parts to his Bean-with-Bacon Megarocket the Vorticons stole. Keen then returned home only to find their mothership hovering above Earth. The second game, The Earth Explodes, finds Keen on board this mothership.

When you start the game, you are presented with a top-down view of the mothership. As you go through it, you will find it resembles the shape of a flying monster. There are different types of rooms (Engine, Weaponry, and Home), and several warning lights that are not used at any point. Your main concern though is the X-14 Tantalus Rays housed in eight of the rooms, aimed at the same cities featured in Where in the World is Carmen Sandiego?. Destroy all eight rays, and you will complete the game.

When you enter a room, the view switches to a side-on perspective, and the aim here is to find the exit, while unlocking a series of doors blocking it. Once you have found the exit and go through it, the entrance will be replaced by a red square with the word “Done” in it, and you can’t enter the room again.

The thing I noticed straight away is the change of graphics. The gray background from the last episode is gone, replaced by nice patterns with a touch of gray to them, and they look like a good match for your next bathroom. The corridors of the mothership contain tiled floors that look like the gray blocks from Arkanoid, while some of the levels have patterns that resemble a chain-link fence.

The items are similar to those in the first episode. With the exception of the Stuffed Toy Vorticon, every item has a food theme. You can get candy bars, hamburgers, chocolate cake, and “Vorta-Cola”. Of these items, the Toy Vorticon has the highest number of points. These stuffed teddy bears are often out of reach, but if you manage to collect two or three of theses, you may find yourself awarded with an extra life. Keen is equipped with his pogo stick which he carried from his last adventure, and this will help him reach items he cannot get to by foot.

There are several creatures to watch out for. Several Vorticon Elite guards are found protecting the Tantalus Rays from intruders like Keen. Other enemies include the guard robot and the Vorticon Grunt. Contact with any of these creatures will result in a loss of life. He can get a raygun that will help him deal with these creatures. Each raygun contains five charges. Since some of the creatures require more than one shot to kill, it is important to stock up on ammo.

The two impressive cinematics are on par with the first episode in terms of quality, and these are worth watching more than once. One of these signals a game over, and is triggered when you flip a switch in one of the Tantalus Control Rooms. The other one occurs when you successfully protected all eight cities.

The Bad
The same problem is present as it is in the last game. You keep firing your pistol by accident because you need to press two keys simultaneously: the [Ctrl] and [Alt] keys.

The Bottom Line
The second episode of the Keen series, in which you have to save certain cities from destruction, has the same gameplay as its predecessor: top-down view for the world map, side-on view for the rest. Even though the sounds and controls are similar, the graphics have been improved, with the background changing from a dull gray to an actual pattern. Like in the last game, you can save the game in one of nine slots, as long as you do it on the world map. Even though that Keen was made in the early Nineties, this game can be played on modern systems due to the fact that there are no timer issues you need to worry about.

DOS · by Katakis | カタキス (43092) · 2021

Small but solid improvements make Keen 2 one of the coolest platformers for the pc.

The Good
Practically the same as the original gameplay-wise, The Earth Explodes is the second and probably best episode in the original CK trilogy. As you came back from Mars at the end of the last game, you happened to notice that the Vorticons had positioned their dog-shaped mothership near earth, and apparently they mean to blow it up! As Commander Keen, defender of the galaxy, Billy Blaze has to get back on his starship and get to the mothership in order to kick some Vorticon ass and save the earth.

As I mentioned, this game is practically the same as CK1, but now you aren't collecting space ship parts, instead you have to explore the mothership and disable it's individual laser guns (each targeted at a different location on earth). I feel that this simple change makes the game much more foccused than it's predecessor and with new and much more intriguing levels and enemies like the fearsome Vorticon warriors, who jump around but remain land-locked when the lights are out (a significant gameplay concept that one has to remember to beat some levels), plus the addition of a much more cohesive background and graphic style (you are after all in a space ship) gets you a much more solid Keen game than it's prequel.

The Bad
Practically nothing, the only bad aspects CK2 has come with the genre, and that's about it.

And the lack of major additions can't be really considered since this was the second episode on an already developed trilogy instead of a "real" sequel (following the standard "first episode free, two others by order" shareware mantra).

The Bottom Line
Probably the most enjoyable of the first Keen trilogy, packed with good, challenging yet balanced gameplay, cute graphics, good clean humor (you can blow up the earth if you want to!) and some great levels and enemies make for a fantastic PC-only platformer.

DOS · by Zovni (10503) · 2003

[ View all 6 player reviews ]


Secret level

Unlike the first and the third episode, this one doesn't have a secret level as the creators thought a secret level on the map of the mother ship didn't feel right.

Information also contributed by Frenkel


MobyPro Early Access

Upgrade to MobyPro to view research rankings!

Related Games

Commander Keen 3: Keen Must Die!
Released 1990 on DOS
Commander Keen: Keen Dreams
Released 1991 on DOS, 2013 on Android, Windows...
Commander Keen: Robot's Revenge!
Released 2000 on Windows
Commander Keen Combo CD
Released 1998 on DOS, 2007 on Windows
Commander Keen: Keen Dreams - Definitive Edition
Released 2020 on Wii U, 2022 on Xbox One, 2023 on Windows...

Related Sites +

Identifiers +

  • MobyGames ID: 217
  • [ Please login / register to view all identifiers ]


Are you familiar with this game? Help document and preserve this entry in video game history! If your contribution is approved, you will earn points and be credited as a contributor.

Contributors to this Entry

Game added by Tomer Gabel.

Additional contributors: Xantheous, Steve Hall, Frenkel, formercontrib, Patrick Bregger.

Game added August 14, 1999. Last modified February 28, 2024.