Accomplish the indicated achievement to get the corresponding number of 
Gamerscore points:

  We Came, We Saw... (50 points): Complete the game on "Casual" or "Experienced" 
  difficulty. 
  Are You A God? (100 points): Complete the game on "Professional" difficulty. 
  Slam Dunk! (15 points): Slam dunk a ghost into a trap. 
  Slime Dunk! (15 points): Trap a ghost using the Slime Tether. 
  Stasis Dunk! (15 points): Trap a ghost using the Stasis Stream. 
  I Ain't 'Fraid of No Ghost! (10 points): Trap a ghost. 
  Aim for the Flat Top! (10 points): Eliminate a creature. 
  Heat 'Em Up (20 points): Purchase all upgrades for the Proton Gun. 
  Mother Pus Bucket! (20 points): Purchase all upgrades for the Slime Gun. 
  We be fast! They be slow! (20 points): Purchase all upgrades for the Dark 
  Matter Generator. 
  I Don't Want My Face Burned Off (20 points): Purchase all upgrades for the 
  Meson Collider. 
  We Have the Tools! (40 points): Purchase all available equipment upgrades. 
  The Destructor (30 points): Complete the game with more than $3,000,000 in 
  property damage. 
  Nice Shootin', Tex! (30 points): Complete the game with less than $100,000 in 
  property damage. 
  ...And You Want to Keep It? (20 points): Collect a Cursed Artifact. 
  Spores, Molds, and Fungus (40 points): Collect all Cursed Artifacts. 
  I'm Picking Up A Signal... (20 points): Obtain a 100% PKE scan on a paranormal 
  creature. 
  Back Off Man. I'm a Scientist (40 points): Obtain 100% PKE scans for every 
  paranormal creature. 
  I'm a Ghostbuster, Not a Doctor! (20 points): Revive your teammates 20 times. 
  I Feel So Funky (5 points): Get slimed by a charging ghost. 
  Total Protonic Reversal (5 points): Knock yourself down with your own weapon. 
  You Gotta Try This Pole! (5 points): Slide down the fire pole. 
  It's Slime Time (20 points): Use the Slime Tether on 15 ghosts. 
  I Looked at the Trap, Ray! (20 points): Recover 20 of your own full ghost 
  traps. 
  Kosher! (10 points): Remedy a dubious food choice to make the bar mitzvah as 
  orthodox as it can be. 
  I Love You When You Rough-House! (10 points): The tidy arcitectural office 
  could use some Proton-based humbling. 
  But the Kids Love Us! (20 points): The children's reading room has a story to 
  tell, but it will take more than your eyes to see it. 
  You Never Studied (10 points): Keep your ears open to learn everything you can 
  about the Civil War. 
  I've Quit Better Jobs Than This. (20 points): Some ghosts had a real blowout 
  in the Coat Room. Clean it up? 
  Hedgebuster (10 points): The hedge maze is a real eyesore; do some Protonic 
  pruning. 
  One down, on the Ground! (20 points): Airborne coffins are an affront to 
  gravity; use your Proton Pack to avenge Mother Nature! 
  Ghostbusters Drinking Game (40 points): Quench your thirst wherever possible 
  to avoid being scared spitless. 
  Loans Paid Off (10 points): More than $100,000 earned in Xbox LIVE. 
  On the Payroll (10 points): Successfully complete one Xbox LIVE campaign. 
  Egon's Guinea Pig (10 points): Use one of every pickup (both power-ups and 
  equipment). 
  Payday! (10 points): Be the overall top earner in each Xbox LIVE campaign 
  setting. 
  It's a Living (10 points): Trap over 50 ghosts in your Xbox LIVE Ghostbusting 
  career. 
  Wanted! (10 points): Defeat three Most Wanted Ghosts. 
  Employee of the Month (10 points): Be top earner in each Xbox LIVE job type. 
  No Job Too Big (10 points): Defeat all Most Wanted Ghosts. 
  Gozer's Most Wanted (15 points): Successfully complete each Xbox LIVE job in 
  every location. 
  Overachiever (15 points): Get over $2,500,000 in Xbox LIVE, over 30 post-job 
  awards, 50 jobs completed.