Limit on weapons used during combat
From the rules reference (page 12):


  Q. Can I use multiple weapons during combat?
  
  A. Yes, but you can only apply the highest bonus to a test. However, 
  you may use any other effects, from your other weapons. For example, 
  if you have a Bull Whip Asset and a .45 Automatic Asset, you may 
  apply the +3 bonus from the .45 to your {combat check} instead of the +1 bonus from the whip, and you may still reroll one die by using the whip’s 
  other effect.