Here is the full list of all 23 Pyroworks achievements.
Be in the same lobby as s1nn3r
Get a tinnitus
Make at least 20 fireworks blow up on the ground at once
Finish the tutorial
Play Pyroworks on New Years Eve
Join a server with at least 10 people in it
Join a singleplayer or multiplayer game for the first time
Shoot another person (don't do this in real life)
Launch a rocket barrage with at least 40 rockets
Make a save which has at least 500 objects
Make a save which has at least 1250 objects
Make a save which has at least 2500 objects
Connect at least 20 fireworks with the fusing system
Light at least 100,000 fireworks
"Accidentally" blow up the hunting tower
Blow up a shell on the ground
Blow up a 16" shell on ground
Find the true meaning of Pyro Energy
Light at least 60 Singleshots in 15 seconds
Use at least 100 cakes in a show
Shoot 5 shells of the biggest caliber at once
Light 25 flares at the same time
Light a groundsalute with at least 200g of flash