Gehenna Dawn — Jay Allan

Book one of the Portal Worlds series, by the author of the best-selling Crimson Worlds series... Jake Taylor was a New Hampshire farmboy who wanted nothing more than to marry his girlfriend, work on the farm, and maybe one day write a great novel. But mankind was fighting the alien Tegeri and their bio-mechanical cyborg soldiers, and UN Central needed men…men to go to war on hostile worlds far from home. Jake wasn't given a choice, not a real one. He found himself torn from home and family, conscripted for life and shipped to the planet Erastus to take his place in the battle lines, never to return. Erastus was a sweltering inferno, called Gehenna by the condemned men sent to fight there. In the blasted deserts and steamy jungles of this alien hell, Taylor and his cybernetically-enhanced comrades fight their never-ending war. As Jake survives battle after battle, he rises steadily through the ranks, giving all to the desperate fight to save Earth. But endless combat in hell carries a cost, and Taylor feels his faith slipping away. He begins to question much of what he's been told, things he'd believed all his life, and the more he learns, the greater his disillusionment grows. He can feel the madness building inside him, slowly taking control. But when he discovers the ultimate betrayal, a secret more horrific than anything he'd ever imagined, he must decide who is the real enemy…and how to contain the fury and lust for vengeance that threatens to consume him. How far will he go to destroy the true evil and right a horrendous wrong? And if he does what he must to prevail against overwhelming odds and win the final victory, will be become the very thing he has sworn to destroy?