Here is the full list of all 15 100 Pumpkins 2 achievements.
Finish the game with more than 10 deaths.
Destroy the final boss.
Complete the map.
Obtain the Running Boots.
Obtain the Double Jump Boots.
Destroy the spider boss.
Find 50.
Destroy the snake boss.
Find the oldest pumpkin. (doesn't count toward the 100)
Unlock fast travel.
Obtain the pitchfork.
Obtain the map.
Finish with a completion time of under 25 minutes.
Find and destroy the secret boss.
Finish the game with 10 deaths or less.