Some weird, some psychopatic, some random. They all came from the Everfree forest. What now ?

The night before Celestia sends her most faithful student to Ponyville, a shooting star wakes the entire town. What was it ? Where did it land ? And what will happen when six crazed mercenaries from outer space pass the peaceful town's gate ?

In a last act of defiance, Discord created a gateway to Tartarus, linking it to Equestria. But what came through it wasn't really expected ...