Here is the full list of all 51 Giana Sisters 2D achievements.
Survive the first level
Collect 100 diamonds.
Collect 1,000 diamonds.
Get rid of 50 monsters.
Defeat 200 monsters.
End the first island.
End the 2nd island.
Bring down a boss.
Transform yourself into the Punk Giana.
Get rid of an opponent with a shot.
Get rid of an opponent with one jump.
Use the chewing gum.
Destroy 50 stone blocks.
Get rid of one owl.
Bring down a killer owl.
Get rid of a bee.
Bring down a killer bee.
Flatten a beetle.
Get rid of a jellyfish
Wipe out an eye.
Collect 5,000 diamonds.
Collect 10,000 diamonds.
Collect 50,000 diamonds.
Collect 100,000 diamonds.
Collect 1,000,000 diamonds.
Unlock a bonus level.
Activate all bonus levels.
Finish the classic levels.
Get rid of 500 monsters.
Get rid of 1,000 monsters.
Get rid of 10,000 monsters.
End the 3rd island.
End the 4th island
End the 5th island
End the 6th island.
End the 7th island
End the 8th island.
End the 9th island.
Play the game completely.
Complete the game without a game over.
Jump in the air 5,000 times.
Use the soda bottle.
Get rid of two opponents by jumping without touching the ground between jumps.
Get rid of three opponents by jumping without touching the ground between jumps.
Get rid of 10 opponents by jumping without touching the ground between jumps.
Destroy 1,000 stone blocks.
Destroy 5,000 stone blocks
Destroy 10,000 stone blocks.
Destroy 100,000 stone blocks.
Wipe out a killer eye.
Get rid of every monster at least once.