QAR: war of quads

After each checkpoint if you have no active effect you'll get positive or negative one and enemy quad will be spawned. So after some time it will be harder and harder to increase your score. The more points you have the greater the chance of getting a positive effect.
List of effects you can obtain:
- speed: inrease your quad speed
- rage: increase enemies speed and activate danger border
- freeze: decrease your quad speed
- slow mo: decrease enemies speed
- deactivate: destroy one enemy
- invisible: your quad ignores enemies
- double points
- quad points
For competition with other players there is global leaderboard via Google Play Game Services. Can you get the top place over the world?