Here is the full list of all 12 Sonic The Hedgehog 2 trophies - there are 8 bronze, 3 silver and 1 gold.
Beat the game.
Beat the game in under an hour.
Stay in Super Sonic mode for one minute.
Become Super Sonic.
Get all the Chaos Emeralds.
Beat Chemical Plant Zone 1 in under 45 seconds.
Get to the Casino Night Zone.
Get one Chaos Emerald.
Beat Emerald Hill Zone 1 in under 35 seconds in single-player or co-op mode.
Clear the Emerald Hill Zone 1.
Win 10 versus zones in online play.
Play all four multiplayer zones.