Kingdom Hearts: 358/2 Days/Awesome

Opening to the Believe mission in Kingdom Hearts 358 Days Over 2, which lets you play out Deep Dive, by giving you the control of a vastly powered up dual-wielding Roxas, who can pretty much One-Hit Kill everything.
- It's more awesome than that, because you still know how it is going to end... but you play it anyway, determined to take down the Organization all by yourself. "Believe" indeed.
On that note, the escape from the Castle That Never Was is pretty awesome too, in which a weakened Roxas takes down Saix, one of the stronger members of the Organization, seemingly without breaking a sweat.

Saix: We don't accept resignations.
Roxas: I've got nothing to say to you.
Saix: Then let's keep this short and sweet.

- Just the dialogue of that is a Moment of Awesome.
- The fight's even better since he's spent the whole game up to this point kicking Roxas and Xion. Now he'll learn.
I am personally a fan of finding out side characters went and saved the world from evil destructive menaces while the main character was taking a Ten-Minute Retirement somewhere (see also: Crisis Core). Because of that, although Xion wasn't exactly threatening the worlds, just Roxas's and Sora's existences, the fact that Roxas defeated a One-Winged Angel-ed up Eldritch Abomination while Sora was out of commission appeals to me very much. It also helps that the entire mission, and the cutscenes surrounding it, were one big Tear Jerker.

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