Prince of Persia: The Sands of Time (2010)

The plot:

The plot on this one is a bit muddied, since it involves time travel, but here we go:

Dastan is an orphan adopted by King Sharaman of Persia and raised as his own son, alongside the King's actual sons Tus and Garsiv. The King's brother, Nizam, serves as the King's advisor. The brothers attack the city of Alamut, believing it is selling weapons to the enemies of Persia. During the attack, Dastan acquires an unusual dagger, and Tamina, the Princess of Alamut agrees to marry Tus to cement the peace.

After the attack, Dastan presents King Sharaman with a cloak which turns out to be poisoned. Dastan flees Alamut with Tamina. They have various adventures, and Dastan learns that the dagger contains the Sands of Time, which can be used to turn back time. Using the dagger to survive attacks on their lives, they learn that the villain is Nizam, who fabricated the reasons for the attack on Alamut so that he could go back to a time when Sharaman's life was in danger and make sure he died, so that Nizam would become king.

At the climax, Dastan and his allies fight against Nizam and his hired Hassansins. Everyone but Dastan dies, pretty much, and Dastan does the thing he shouldn't do: plunge the dagger into the Sandglass from which the sands are obtained and open it up, allowing time to flow freely. Dastan reverses time to the point where Alamut is taken, prevents the death of Sharaman, exposes Nizam, and ends up with the dagger and the girl.

Fitting it into the WW4C:

The star of this movie, for purposes of the WW4C, is really the Dagger of Time. Anyone who has possession of it can reverse time, undoing moments, days, or even years (as Nizam wanted to do). It doesn't make its wielder invincible, but it does give them a lot of second chances to get things right. From a game standpoint, though, the only person who knows time has been reversed is the wielder, so the wielder just looks like he's supercompetent.

Also of note are the Hassansin, which appear to be just Assassins, but with weird powers. Zolm, the leader of the Hassansin, appears to be able to control serpents. All superhero universes seem to need a secret villainous organization based around a snake theme, and so I'm going to take the Hassansin, call them the Assassins, and use the snake theme for them. (Even though I've grown accustomed to the Assassins being the good guys after the Assassin's Creed video games.)