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"

Trophies
Successfully complete one of the following tasks to get a trophy:

Train Catcher (Bronze): Finished 'Loco Motives'.
Off the Hook (Bronze): Finished 'Hold the Phone'.
Defeat Zurg (Bronze): Finished 'To Infinity and Beyond'.
Carnival Conqueror (Bronze): Finished 'Fair Play'.
Rocket Launcher (Bronze): Finished 'Witch Way Out'.
Making a break for it (Bronze): Finished 'Hide-N-Sneak'.
Mashing the Masher (Bronze): Finished 'Trash Thrash'.
Muffin Massacre (Bronze): Finished 'Muffin to Fear'.
Mapnipulator (Bronze): Explored all the objects on the map.
Welcome to Town (Bronze): Finished the Woody's Roundup tutorials.
First Sale (Bronze): Buy a toy from the Toy Store.
Pict-O-Amateur (Bronze): Complete 1 disc of Pict-O-Matic missions.
Pict-O-Collector (Bronze): Find all 6 discs of Pict-O-Matic missions.
Pict-O-Master (Bronze): Complete all Pict-O-Matic missions.
Spooky Town (Bronze): Purchase Sid's Haunted House.
Cuddly Town (Bronze): Purchase Lotso's Enchanted Glen.
To Infinity... (Bronze): Purchase Zurg's Spaceport.
Airborn Ranger (Bronze): Hit 15 Paratrooper targets.
First Bronze (Bronze): Earn a bronze medal in a vehicle challenge.
First Silver (Bronze): Earn a silver medal in a vehicle challenge.
First Gold (Bronze): Earn a gold medal in a vehicle challenge.
Sneaky Sneaky (Silver): Finished the Prison Break without ever tripping an alarm.
Space Ranger Elite (Silver): Reach Zurg's base without losing all your health.
True Carny (Silver): Achieve gold on all carnival games.
No Toy Left Behind (Silver): Rescue all the orphans on the Train.
We can rebuild him (Silver): Collect all of Zurg's Parts.
Memories (Silver): Collect all of Andy's Memorabilia.
Townspeople Hunter (Silver): Find all the hidden townspeople.
No Claw Required (Silver): Find all the hidden aliens.
Really holding all the cards (Silver): Find all the Special Cards.
Holding all the cards (Silver): Find all the Regular Cards.
Toy Collector (Silver): Purchase all the items in the Toy Store.
The Collector (Gold): Gather every collectible in the game.
Gold Super Star (Gold): Collect all the Gold Stars.
Photo Journalist (Gold): Complete all the Toy Camera missions.
Toy Story 3 Champion (Platinum): Congratulations-you've earned all the trophies for Toy Story 3!

Additionally, there are three secret trophies:

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

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