Seth's sword was called Brightblade in the English version. If you asked him about the 'gaudy' name, he would tell you it was given to him by an old wizard, who said when he discovered the meaning for its name he would have reached his life's destiny. I wonder if his destiny was to wait 75 years (or so) to challenge a dragon knight to a duel on a bridge (in Divinity 2), or if he figured the name out before then? If the latter, that knowledge certainly didn't help him much.
