Speed Demon
Common60.1%ObjectiveOptionalAnywhere
Completely fill and then empty your Rocket Boost 10 times in a single match
There are 6 orbs around the pitch; in each corner and diagonally opposite to the goals - picking up one charges the boost to 100%. Then hold the boost button to empty it. This is easiest done in a bot match when you've already got whatever points/goals/lead you need and you just want to keep the ball in play until the end.