Elfistra the Sorceress

Deep within a forest in the Northern areas of England, there is a deafening electrical crack! The hunters are thrown off their horses as a column of white light, a portal, opens up before them. A strange looking red arrow shoots out of the column and buries itself in the eye socket of one of the hunters. He is dead before he hits the ground. Hugo turns to run as more arrows zip past either side of his head. He trips and slides along the forest floor as he hears voices, in an unusual language he has never heard before, flood his head. Dazed, he picks himself up and notices some tall beings running towards him. Hugo notices the tops of their ears are pointed! One of the beings gestures towards Hugo and telepathically issues a command. Immediately a numbness begins to spread throughout Hugo's body as he collapses, semi-consciously back onto the forest floor. Two of the beings grab Hugo underneath his arms and roughly drag him back and into the column of white light. Why has this portal appeared? What danger does it bring to Earth and its inhabitants? What lies on the other side of the portal?