Lightning Lynx was once a member of the Raiju Clan until he was utterly exiled for his defeat against the Bride of Conquering Storm.  Since then, he became a member of the Fearsome Four and eventually the Destructix, working with many criminals against the Freedom Fighters.  However, after the Clan Wars had ended, Lightning was summoned back to the Raiju Clan under the Iron Dominion's rule.  He was also the one to bring Espio back to the Shinobi Clan.

From a few impressions that I've heard of Lightning, he seems to be speaking with a Japanese accent.  While I do recommend it, I won't hold it against you if you can't do it.  If you'd rather stick with a North American accent, it's fine by me.  However, I would prefer if you made him sound a bit youthful because that's how I imagine him to sound whenever I look at him.