Complete the following tasks to unlock Vita trophy rewards.

Trophy	How to unlock
Assault (Bronze)	Kill 10 Aliens.
Burn, Baby Burn (Bronze)	Defeat A Boss Alien Together With Flamethrowers.
First Blood (Bronze)	Make Your First Kill.
Hard As Nails (Bronze)	Complete Alien Breed.
He Shoots, He Scores (Bronze)	Score 1,000,000 Co-Op Points On A Level.
Isr4-C (Bronze)	Complete 17 Co-Op Games.
Locked And Loaded (Bronze)	Purchase All Weapons From The Shop.
Never Get It Back (Bronze)	Watch The Alien Breed Prologue.
Ripley (Bronze)	Flame 1000 Aliens.
Roxanne (Bronze)	Kill 50 Aliens During A Countdown.
Run, Stone Run! (Bronze)	Complete Alien Breed Level 2 Without Firing Your Weapon.
Saving Ammo (Bronze)	Kill 2 Aliens With One Shot.
Scavenger (Bronze)	Collect Every Pickup On A Level.
Seconds Out (Bronze)	Reach An Exit Deck Lift With 1 Second Remaining.
Smashing (Bronze)	Die Together In The Mashers On Convergence Level 4.
Teamster (Bronze)	Score 17,171,717 Points Total Single Or Co-Op Play.
There's No I In Team (Bronze)	Complete A Level In Co-Op.
Tread Carefully (Bronze)	Complete Alien Breed Se Level 11 In Co-Op Without Tripping The Alarm.
Warming Up (Bronze)	Kill 100 Aliens.
Who's The Boss? (Bronze)	Defeat A Boss Without Firing The Assault Rifle.
You're Only Supposed To Blow The Bl**dy Doors Off (Bronze)	Complete A Level Using No Keys.