You galloped across the dead sea bottoms of Mars,
Flew through the Everest-tall trees of Venus,
Sweated in the Twilight Zone of Mercury
and sought romance on a moon of Jupiter.
The Moons of Kerogo haunt your waking hours,
Night after endless night you hear their call,
Again, it is time to take up your sword:
Adventure and Romance await you.
In the paleolithic an alien race, the Archon, kidnapped cavemen and took them to the Moons of Kerogo. In these laboratories they were twisted as the Archon tested the genetic plasticity of our race and others. Then the Archon warred with an enemy they could neither defeat nor stop. After the Archon's extinction the humans and other races escaped the laboratories and preserves to spread across the surfaces of the moons.
But the escaped races relied upon the technology of the Archon to build their civilizations. As the devices wore out every generation saw the slow retreat to barbarism and savagery. In the last age an expedition accidently activated a comatose Archon AI. It ordered Living Metal, its robots, to restore the laboratory moons of the Archon. to capture enough specimens of the escaped races and exterminate the rest.
In the genocide some managed to escape and reach temporary refuge. But Living Metal continues to restore the moons. Mankind can only hide for a few more generations before he is again hunted. Many humans are hiding as savages. The civilized ones are in warring city-states.
Mankind needs men of vision. Men who can forge empires where art, science, technology and the tools of war can be created to fight the Living Metal of the Archon. It is a time for heroes...it is your time.
To power this exotic world of adventure the simple, yet elegant, die versus die system was created. Characters are created by using starting points to buy skills at a certain die level (d4-d12.) Challenges, foes and tasks are all represented by a single die too. There are no modifiers. When a conflict comes up the character's die is rolled against the opposing die (say d6 versus d8) and the high number wins. The difference is the points of damage (if applicable or simple failure) to the loser. After that the next round begins.
This die versus die mechanic is used throughout. The game system can be explained to new players in 30 seconds. It helps the game master to assign challenge die to unexpected player actions or questions during the game session. Another effect is to make game preparation quicker so more time can be spent gaming or fleshing out the scenario.
To further help the game master a complete world (Zardoon) is presented. Twelve warring city-states, four human races, four alien races, six Orders of Good, six Cults of Evil, maps, language conventions, advanced alien technology with adventure seeds presented with each of these to help the game master with adventure ideas. Included is a starting adventure.
Planets of Peril is a complete game in one book. Nothing else to buy except a single set of polyhedral dice.