Here is the full list of all 14 Retro City Rampage: DX trophies - there are 11 bronze, 2 silver and 1 gold.
Kill 256 civilians within a single life
Hit 4 people with a single shotgun blast
Play Free Roaming Mode as one of the guest stars
Blow up 8 vehicles in 8 seconds
Drive 65,536 pixels
Knock someone off their bike to ricochet another off theirs
Get "sick" on "milk"
Kill four green sewer dwellers
Raise your threat level by committing a crime that attracts police attention
Reach a 99X chain multiplier
Hit 25 pedestrians in a row with your car without stopping
Match all cards in a single round of the casino game at the Spades To Steal Casino
Dethrone GLC's high score
Collect all of the time machine parts