Bonus weapons
Successfully complete the indicated level in Story mode to unlock the corresponding weapon for purchase at the shop for the listed price:

Cow Cannon ($2,500): "Get Cows To Higher Ground"
UFO Gun ($2,000): "Blow Up The Dam"

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

Train Catcher (10 points): Finished "Loco Motives".
Off the Hook (10 points): Finished "Hold the Phone".
Defeat Zurg (10 points): Finished "To Infinity and Beyond".
Carnival Conqueror (10 points): Finished "Fair Play".
Rocket Launcher (10 points): Finished "Witch Way Out".
Making a break for it (10 points): Finished "Hide-N-Sneak".
Mashing the Masher (10 points): Finished "Trash Thrash".
Muffin Massacre (20 points): Finished "Muffin to Fear".
The Collector (120 points): Gather every collectible in the game.
Mapnipulator (10 points): Explored all the objects on the map.
Sneaky Sneaky (25 points): Finished the Prison Break without ever tripping an alarm.
Space Ranger Elite (25 points): Reach Zurg’s base without losing all your health.
True Carny (25 points): Achieve gold on all carnival games.
No Toy Left Behind (25 points): Rescue all the orphans on the Train.
We can rebuild him (25 points): Collect all of Zurg's Parts.
Memories (25 points): Collect all of Andy's Memorabilia.
Townspeople Hunter (25 points): Find all the hidden townspeople.
No Claw Required (25 points): Find all the hidden aliens.
Really holding all the cards (30 points): Find all the Special Cards.
Holding all the Cards (50 points): Find all the Regular Cards.
Welcome to Town (10 points): Finish the Woody's Roundup tutorials.
Gold Super Star (100 points): Collect all the Gold Stars.
First Sale (5 points): Buy a toy from the Toy Store.
Toy Collector (50 points): Purchase every item in the Toy Store.
Pict-O-Amateur (25 points): Complete 1 disc of Pict-O-Matic missions.
Pict-O-Collector (25 points): Find all 6 discs of Pict-O-Matic missions.
Pict-O-Master (50 points): Complete all Pict-O-Matic missions.
Spooky Town (10 points): Purchase Sid's Haunted House.
Cuddly Town (10 points): Purchase Lotso's Enchanted Glen.
To Infinity... (10 points): Purchase Zurg's Spaceport.
Airborn Ranger (10 points): Hit 15 Paratrooper targets.
First Bronze (5 points): Earn a bronze medal in a vehicle challenge.
First Silver (10 points): Earn a silver medal in a vehicle challenge.
First Gold (25 points): Earn a gold medal in a vehicle challenge.
Photo Journalist (15 points): Complete all Toy Camera missions.

Additionally, there are three secret achievements:

No Swimming (25 points): Blow up the dam and expand your town.
Rescue Space Ranger (40 points): Save Mayor Hamm from the bandits.
Give Me My Gold Back (75 points): Defeat Mayor Hamm in the Woody's Roundup boss battle.

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