Here is the full list of all 21 BlazeRush achievements.
Destroy 50 cars with the autogun
Complete all career missions
Destroy 20 cars with a soundwave
Defeat the boss
Kill the opponent with each weapon but the slime
Unlock all cars in career
Rise from the last spot 5 seconds before the finish
Break the sound barrier
Spend 2 seconds in the air
Overtake the leader a second before the finish
Hit yourself with every possible weapon
Drop a slime while in the lead
Be the king for most of the race
Die a hundred times
Win in each of the three modes
Destroy 40 cars with the saw
Destroy 30 cars with the missile
Be the leader and lose it all 5 seconds before the finish
Complete your first serious competition
Do a NO SCOPE, while doing a 360
Join an online party