Here is the full list of all 41 Popcorn Rocket achievements worth 1,000 gamerscore.
Finish Stage 1: A Slice of Pie
Finish Stage 2: The Cookieroid Field
Finish Stage 3: Tutti Fruity Kablooey
Finish Stage 4: Special Delivery
Finish Stage 5: Vegetarian Vortex of Doom
Finish Stage 6: Morning Fiber in Space
Finish Stage 7: Don't Eat the Meat
Finish Stage 8: Get Your Cake and Eat it Too
Finish Stage 9: The Greatest Gourmet in the Galaxy
Finish Stage 10: The Final Feast
Get a score of 500,000 in the Main Campaign
Get a score of 1,000,000 in the Main Campaign
Get a score of 2,000,000 in the Main Campaign
Defeat 300 Enemies in the Main Campaign
Defeat 1500 Enemies in the Main Campaign
Defeat 2000 Enemies in the Main Campaign
Get 500 Popcorn Combos in the Main Campaign
Get 1000 Popcorn Combos in the Main Campaign
Get 2300 Popcorn Combos in the Main Campaign
Defeat 1200 Enemies in the Main Campaign with Infinite Lives and Ammo Mode
Defeat 2700 Enemies in the Main Campaign with Infinite Lives and Ammo Mode
Defeat 3500 Enemies in the Main Campaign with Infinite Lives and Ammo Mode
Get 1300 Popcorn Combos in the Main Campaign with Infinite Lives and Ammo Mode
Get 1700 Popcorn Combos in the Main Campaign with Infinite Lives and Ammo Mode
Get 2500 Popcorn Combos in the Main Campaign with Infinite Lives and Ammo Mode
Beat all Bosses In Boss Rush Mode
Beat all Bosses in Consecutive Boss Rush Mode
Finish the main campaign with Infinite Lives and Ammo Mode
Beat all Bosses in Boss Rush with Infinite Lives and Ammo Mode
Finish Consecutive Boss Rush with Infinite Lives and Ammo Mode
Get through all of Blooper Theatre
Last 30 Minutes in Endless Pop Mode
Last 1 hour in Endless Pop Mode
Last 2 hours in Endless Pop Mode
Destroy 500 Enemies in Endless Pop Mode
Destroy 1500 Enemies in Endless Pop Mode
Destroy 3000 Enemies in Endless Pop Mode
Get 600 Popcorn Combos in Endless Pop Mode
Get 1700 Popcorn Combos in Endless Pop Mode
Get 3500 Popcorn Combos in Endless Pop Mode
Get all Achievements