the first one where they say Noctis goes to sleep to gather the powers of the ring, wakes up older and with longer hair and fights Ifrit before Ardyn, who is the final boss(and the first king of Lucis, oh yeah, and is thousands of years old). This person said Luna dies fairly early and that Gentiana is actually Shiva in human form.
The Kingsglaive spoilers have one saying that Regis made a pact with three gods to keep the powers of the waning crystal strong, in turn for the sacrifice of Noctis on his 15th birthday, which he refused and the three gods cursed the land, as well as appointed Ravus the job to kill Noctis. Glauca is Cor's brother, Clarus is the one that betrays the kingdom, Crowe survives and forms a rebel group that you meet in the game. Luna escapes, only to be captured by Ravus, her brother, and is taken to Altissia. Gentiana is Leviathan in human form.
The second rumor is that the ring of Kings can only be used by the Lucis royal family, and others who try to harness the powers are killed(Nyx is granted the use of the powers by Regis, which only last until dawn when it takes Nyx's life). Glauca is Drautos, Niflheim orchestrated everything regarding the invasion, Claurs is good and dies protecting Regis, and there are a lot of members within Kingsglaive that betray Lucis.
I'm wondering where the truth lies. The first Gamefaqs rumor had a lot of people believing it because the call on the Trail of the Titan demo, as well as the longer haired Noctis seen in the E3 trailer. Still, they didn't talk in depth about other important things, like those three gods which are supposed to be significant to the plot.
Kingsglaive rumor #1talks about the significance of the three gods and the goddess of dawn.
Kingsglaive rumor #2 says nothing about the gods, but talks about the inner turmoil amongst the Lucian ranks.
They are suspiciously not showing the opening to journos...
