Impossible Creatures

aka: Bukesiyi zhi Shengwu, Sigma, Sigma: The Adventures of Rex Chance
Moby ID: 8461

Description official descriptions

Impossible Creatures is a real-time strategy with a twist. Rather than building "Unit A" and "Unit B" like nearly all other real-time strategies, in this game the player acquires DNA from animals and mesh them together, creating unique hybrids of two separate animals. Use the strength of a bull, with the speed of a cheetah and the player might have a Cheebull, or give a skunk an extra defense and mix in a porcupine, making a Porskunkine. With dozens of different animal DNA to combine, there are nearly endless combinations.

The main campaign's storyline is something like this. Your father, whom you've not seen since your childhood, sends you a letter in which he says he does not have long to live, and there is a secret he must tell you before he passes on. So you head to one of the uncharted islands in which he works, but you're suddenly ambushed by half-wolf, half-scorpion freaks of nature. Using the creature workshop and DNA collected from the animals, you must create hybrids of your own to rescue your father.

Each creature hybrid has several areas of the body in which can be meshed together. The head, pawns, legs, back, rear, can all be attributed by either of the two creatures involved in the mix.


  • 不可思议之生物 - Simplified Chinese spelling

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Credits (Windows version)

139 People (117 developers, 22 thanks) · View all



Average score: 72% (based on 41 ratings)


Average score: 3.3 out of 5 (based on 19 ratings with 2 reviews)

Too bad the interesting premise is wasted on a generic boring RTS

The Good
The interesting premise, mix-and-matching creatures, could have made a very interesting game. The initial cutscenes were well-made, making the trite and cliche story (not unusual for a game) more interesting.

The Bad
Unfortunately, the "mix and match" creature system is all window dressing, as units are artificially forced into generic roles as melee attackers, missile attackers, or artillery. 90% of possible unit combinations are inferior to the "best" ones, and none allow any really innovative tactics. Not only are unit behaviors not affected by their "ancestry", they aren't even that smart - non-melee units never try to keep the range open, etc. Everything else is about the norm for a RTS game - that is, boring, with tactics dictated by your mouse skills and the only nod to strategy being resource management.

The Bottom Line
Nifty if you want to see interesting creature models. Otherwise yet another (ugh) RTS.

Windows · by weregamer (155) · 2003

Excellent Idea, But Could Be Improved

The Good
Obviously the best part about this game is the ability to create your own custom units (I know I've always wanted to do that) like giant flying lobsters. It is also fun to see all kinds of different units fighting one another. Graphic wise, the game is excellent and despite constantly having hundreds of units on the screen, the game still runs very smoothly, even on slower computers. Also, you can fight your custom units against other people's creations in multiplayer, which is quite fun.

The Bad
Unfortunately, the only thing different in this game from most other strategy games is the ability to create your own units. Not much difference elsewhere. Once the novelty factor wears off, all you're left with is just another strategy game. You can only combine two creatures to form another creature. It would definately be better if more than two creatures can be combined. There's a resource in the game, electricity, which I don't think even does anything. If you build a few lightning rods (they're really cheap too), the electricity will be increasing so much that you can basically ignore it and concentrate on mining coal.

The Bottom Line
If you are truly a fan of the strategy games genre, you might consider buying this game, otherwise if you get bored easily, try something else.

Windows · by Black Death (6) · 2003



There is an add-on for the game, Impossible Creatures: Insect Invasion, available from Relic's official IC site for free (size: 88 Mb).


The game's graphical rendering engine is called SPOOGE. There is a separated physics/collision, AI/script, and combiner engine too.


During development, this game actually underwent no fewer than two official name changes, first from just plain Sigma to Sigma: The Adventures of Rex Chance and then finally to Impossible Creatures as we know it now.

Information also contributed by Rev-san


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  • MobyGames ID: 8461
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Contributors to this Entry

Game added by kbmb.

Additional contributors: Roger Wilco, PCGamer77, Unicorn Lynx, Sciere, Dave Mednick, Cantillon, Patrick Bregger.

Game added February 20, 2003. Last modified January 26, 2024.