Warning spoilers for Twilight Kingdom.

Crossover with Fate/StayNight and Elfen Lied

Dragged by his friends to America's Comic Con. A British guy goes dressed as Gilgamesh the King of Heros, while his cousin goes dressed as Lucy from Elfen Lied. When his replica of Ea that he purchased from weird hooded guy at a store back home begins glowing. He and his cousin suddenly find themselves in Equestria with the power of the King of Heros and the Queen of the Diclonius at their disposal one sets out to do as he pleases while the other seeks to find the knowledge that could bring them home. But they are eventually sealed away by the Alicorn sisters.

Now a thousand years later, before they decide to transfer their Alicorn magic to Twilight for safekeeping the Princessess decide to release an ancient foe that they imprisoned just over a thousand years ago. Gilgamesh who originally ruled of the Crystal Empire before Sombra. They hope to bargin with Gilgamesh so that he would defeat Tirek, but what will this human with the power of the mighty King of Heros do after over a thousand years of imprisonment?