I just started watching Mirai Nikki.
So far i'm on Ep 6, and this serie is something else. (in a good way)
Sometimes it's surprising, like a didn't expect this to turn out as a survival game and sometimes it's obvious, like that Yuno was a cold-blooded killer but they reveal it in a appealing and interesting way.
In other word, So far so good.
How i think it's gonna end: (i haven't read the manga)
Ending 1. He will convince Yuno (1) to ignore Yuno (3) and they will either live in world 3 or 2. (even 1 if possible)
Ending 2. He will kill Yuno (1) and become god, after that he will start living in world 3 with Yuno (3).
Ending 3. He will kill Yuno (3) and be together with Yuno (1),(same as above).
Ending 4. Yuno (1) kills herself to make Yukki god.
Ending 5. Both dies........
In all the endings Murmur dies.