Get the weapons destroy the baddies
You get a new weapon for every 40 enemies you hit in a row, heres a break down of thwe 3 available weapons:
Rapid Fire - The default weapon is a fully automatic high powered energy weapon. Whilst it may not seem very powerful at first once powered up it becomes an incredibly powerful weapon. At full power it shoots 1200 shots per minute and can devestate an enemy squadron in seconds.
Laser Beam - Fires a single shot energy stream that can carve through almost any enemy in a single shot. Even when not at full power this weapon will easily destroy any small enemy that gets in it's path. Shot for shot the most powerful weapon in the game, but has by far the slowest fire rate, ideal for the player who likes to pick his shots.
Twin Shot - The Twin Shot fires two high energy beams side by side to create a wider burst than any other weapon. The Twin Shot makes taking out single enemy with one shot the easiest of all the weapons and because of this its the best weapons to reach a high combo count. When fully powered it shoots 600 shots per minute.