Doomsday Game - Apocalypse Duology, #3

Rescued from post-apocalyptic parallel universes, the Pathfinders have one thing in common: they're all the last man or woman on Earth, but different Earths. They explore dead universes for data, weapons, and technology using "transfer gates" abandoned by a long-vanished civilization. It's risky work, but better than waiting to die, alone, on a blasted ruin. Climate collapse, nuclear winter, world-ending plagues-all in a day's work.
But something odd is going on: people are seeing things that aren't, or shouldn't, be there. Toxic rain is literally driving people crazy. And someone's been taking secret unauthorized trips to an off-limits parallel. It means they're in danger-and ahead of them lie worlds rendered lifeless by rogue singularities or littered with ancient and perilous ruins. There are a thousand ways a world can die-but the threat of their own extinction is never far away."One of the top SF writers active today .