100 heads - rainbow blood
200 heads - You can play as the test versions of the JFG characters. They're kids.
300 heads - The ants turn into snowmen with shorts. At least thats what they look like.
Bonuses
If you get a gold rating on all floyd missions, you can play as the cyborg drone in multiplayer mode.
If you beat the arcade games in the Big Bug Fun Club on Ichor in short times (under 30 sec. for the 1st game and 40 sec. for the second game) you get the track from Diddy Kong Racing, Greenwood Village, in multiplayer mode. If you come in 1st on them you can play the track you beat.
You can get the Mizar racetrack by coming in 1st on the track in Mizar's Palace.
