The big battlescene in the beginning of DragonAge was quite epic.

I think the epic feeling comes when a game makes an intermediary stop,
and switches to a movie-cinematic with some heavy important battle scene, crashing (evil) structure or conversation
between core world-characters.

In Hollywood Adventure movies, ther is always an evil temple
that was crashing in in the final scenes.

But in the end, most Gamestories try to make the player actions
have an epic, world saving outcome.
It gets repetative.