I'm thinking "IRS" will strike fear into the hearts of many.
Or maybe....
Rottweilers
Tsunami
Demon Spawn (that would be my childrens' team name)
Department of Defense
Runny Noses
Ohio E. Coli (terrifying I know)
Or my personal favorite..... The Mad Cows.
Good luck on your quest because my team will beat your team, or something like that...lol