A serious short with sprites? Don't make me laugh. No, literally, don't make the people laugh, because this flash is seriously good!
One thing that I thought of as cool was the Hans Zimmer soundtrack, an excellent composer and selection of tunes for setting the mood in a melodramatic war epic. The script, while occasionally stale, shines through in its timing and cinematic sleekness. This tale is in a compact file size, clocking eight minutes of showtime with a good mixture of dialogue and action. And since it is fully 8-Bit retro, that adds to its charm.
Continue with your fourth part (the end of the series, I imagine?) and never be a stranger with other projects in flash at Newgrounds.