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