Frank Horrigan, walking tank and super soldier of the Enclave, ends up in Equestria of all places when he is defeated by the Chosen One. At the end of each chapter, you make the decision for what Frank does in the next chapter!
When an army of horrible black and red alicorn OC's threaten Equestria, it's up to a group of space marines to purge those xeno scum. The Sunshine Smiles space marines, that is.