Tier 5 in this game.
A cool couple tips is 6 SMGs or Cannons is only the amount you need, as the maximum fire rate is 6 guns and if you have 8 or 10 then only 6 will fire at a time.
Another is spamming Q when you see an enemy is pretty good, scouts them and gets you some extra points.

These shields are super effective also so i recommend using them once they are unlocked.