What the heck is up with that place?
The huge statue at the end looks like the God of Creation, and with the weird cutscene, I'm all confused.

So anyways, what is the Stone of Sealing for? It doesn't really look like much. And could anyone tell me what the entire story of it is? The cult thing?

The Isamat Urbur men are members of some weird cult whose goal is to let their souls become runestones. The only way to do this is to die, which is why when you kill a cultist they turn into a runestone. The statue at the end probably is one of the gods, but is not important at all to the game. The Stone of Sealing helps you achieve the "good" ending of the game. If you do not have the Stone of Sealing, you get the "sad" ending of the game. In order to get the "good" ending, you must have the Stone of Sealing by the Royal Tower, Lower level. During the cutscene at the end of the level, Tara will give the Stone of Sealing to Sol, which will keep him alive in the battle. This will trigger the "good" ending. All in all, the Stone of Sealing is not necessary, and it is personal preference that determines which ending you want, because the ending does not affect anything.