The fires in Foehan.
The Rift was a large tear in the sky that threatened Oberin in the Year 432. On the last day of the Bleeding Moon of that year, Oberin was hit by a thunderstorm and earthquake of huge proportions. After this disaster, the night sky was torn open, creating the Rift.
A massive bolt of energy descended from the Rift, striking the forest near Foehan and creating a large blaze that quickly became out of control. An ominous voice of unknown origin announced menacingly that the path had been opened so that the Rift could expand and Creation could be purified.
A large group gathered to extinguish the fires. After they succeeded in doing so, they met a woman hiding in Foehan. The woman claimed to have seen where the earth had been struck, leading the humans to a small spot to the northeast of town. There they fought an army of undead which had been gathering around a strange and horrifying ritual marked by runes and human corpses.
There, the mysterious voice was once again heard, this time calling for its Emissary to purify the lands. This emissary turned out to be a fearsome Abyss Dragon. A long battle ensued between the dragon and the humans present, and it was eventually won by the humans with the help of Birek McCalla, Altaira Mei and Hayate. Following the death of the dragon, the rift narrowed, despite more warnings from the voice.
The death of the Emissary Abyss Dragon.
As the Red Moon waxed, the occasional bolt of lightning shot forth from the Rift. These bolts brought with them many Fire Elementals, Rust Beasts, Red Dracos, Poison Beasts and Gapers. On one occasion, a powerful gaper that became known as a Void Watcher emerged, as well as a Void Beast. The appearances of these two unique creatures led many to believe that the Rift was a portal to the Void. Many also suspected that the Rift had something to do with the return of the Legion.
Then, still in the early phases of the Red Moon, the Rift widened and the land once again become covered in darkness. Two enormous bolts of lighting struck the cemeteries of both Lerilin and Mirith. Hoards of undead were fought in both cemeteries, with a Lich found at each one. At the bottom of the Mirith Crypt, what appeared to be two Abyss Dragons were found in the two cells at the end of the hall. However, they weren't actually present and flickered away. They were called Void Images, and they seemed to have been watching the action. Once the Liches were killed, the Rift shrank in size, although it was still bigger than it was before the incidents at the cemeteries.
The ritual grounds near Foehan.
Immediately following, the group returned to the ritual grounds just as Beleth appeared to inspect the area. He examined the runes, noting that four of them had not yet been used. Beleth was even more disturbed by the existence of the unused runes, as he thought that an unused rune could only last for a few minutes. The only thing that he was certain of was that the runes fueled the Rift, which was growing bigger by the hour. Confused, Beleth left to report to the King.
Attempts to speak with Marthonis resulted in some more information about the Rift. Marthonis believed that the Rift was a reaction to some other event, and that there was some opposition between higher powers in Oberin. He couldn't specify who the higher powers were, aside from the fact that they were not gods. The only thing that became clear was that Marthonis knew things about the Rift and that he didn't open it himself.
Later, in the Lucky Moon, Marthonis and Beleth met at the ritual place. Beleth seemed to learn more about the origins of the Rift from this meeting. But before he could publicly reveal what he had learned, an incident with a member of the Marali Vanguard occurred and Beleth left the scene.
Since then, there has been no trouble with the Rift. It has appeared to have grown stable. However, one can never be too sure about such matters...