Orson Scott Card

An expert at simulated war games, Andrew "Ender" Wiggin believes that he is engaged in one more computer war game when, in truth, he is commanding the last Earth fleet against an alien race seeking Earth's complete destruction.

To prevent the destruction of his planet, teenaged Rigg Sessamekesh, who can manipulate time, must assume more responsibility when he and others travel back 11,000 years to the arrival of human starships.

In the aftermath of his terrible war, Ender Wiggin disappeared, and a powerful voice arose: The Speaker for the Dead, who told the true story of the Bugger War.
Now, long years later, a second alien race has been discovered, but again the aliens' ways are strange and frightening...again, humans die. And it is only the Speaker for the Dead, who is also Ender Wiggin the Xenocide, who has the courage to confront the mystery...and the truth.
Speaker

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Follows the life of Ender Wiggin's comrade Bean, from his escape from the mean streets of Rotterdam, to his student days at the Battle School, and to his role as Ender's right hand ally, strategist, and friend in the epic struggle to save Earth from alien invaders.

One hundred years before Ender's Game, the aliens arrived on Earth with fire and death. Earth Afire by Orson Scott Card and Aaron Johnston is the story of the First Formic War.
Victor Delgado beat the alien ship to Earth, but just barely. Not soon enough to convince skeptical governments that there was a threat. They didn't believe that until space stations and ships and colonies went up in sudden flame.
And when that happened,

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A latest entry in the Ender's Game prequel series follows an invasion of terraforming aliens on Earth, which is complicated by politics and power struggles until a small band of humans organize a desperate defense.

"In this sequel to The Lost Gate, bestselling author Orson Scott Card continues his fantastic tale of the Mages of Westil who live in exile on Earth. Here on Earth, Danny North is still in high school, yet he holds in his heart and mind all the stolen outselves of thirteen centuries of gatemages. The Families still want to kill him if they can't control him...and they can't control him. He is far too powerful. And on Westil, Wad is now nearly powerless--he...

This huge collection of short stories by one of science fiction's most beloved and popular writers is sure to please his millions of fans. Keeper of Dreams contains 22 stories written since 1990. From the opening science fiction tale, "The Elephants of Poznan," we see the hand of a master at work making a familiar idea new, strange, and wonderful. "Angles" takes a sideways look at alternate universes. "Geriatric Ward" is published here for the first...

Lanik Mueller is a "rad"—radical regenerative—a freak who can regenerate injured flesh...and trade extra body parts to the Offworld oppressors for iron. On a planet without hard metals, or the means of escape, iron offers the promise of freedom through the chance to build a spacecraft. But it is a promise which may never be fulfilled, as Lanik uncovers a treacherous conspiracy beyond his imagination. Now charged with a mission of conquest—and...

A sequel to "Ender's Shadow, " in which the child-warriors, heroes of the Formic War, have returned to their families on Earth only to become the pawns of nations who want to use them as weapons in their quest for sovereignty.