A Half-Life 2 Adaption/Crossover.

When an evil from beyond the realm of nightmares descended upon the world they found themselves unprepared. Abandoned by their only hope of salvation and unable to repel the invaders they fell to the darkness and the world as they know it was destroyed. Years later, a power once thought lost to the fog of time and war returns, igniting the spark of revolution in the hearts of the downtrodden.

"Rise and shine, my friends. Rise and shine. Not that I wish to imply you have been sleeping on the job. No one is more deserving of a rest. And all the effort in the world would have gone to waste until... well, let's just say your hour has come again. The right mare in the wrong place can make all the difference in the world. So, wake up, little ponies. Wake up and smell the ashes"

When fortune hunter Nathan Drake discovers a secret operation on a remote island he unknowingly sets a two thousand year old plan in motion. Drake finds himself thrust into a a new world he didn't know existed and his only hope of return lies in the hooves of forces be barely understands.

Mountain Snow, Frostbite, The Shadow, The Silent Storm, etc. none of these names appear in official records, however they are enough to strike fear into the hearts of all but the most hardened soldiers. He is an outlaw and hardened thief with an enigmatic past and unknown goals.

Twilight Sparkle, princess Celestia's prized pupil and the element of magic.

When fate brings these unlikely two together each one must come to terms with their own gripping realization about their existence and if what they believed in actually mattered.