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