Here is the full list of all 10 NekoChan Hero - there are Collection achievements.
Find all the special coins
Reach the end of the level with the bike
Save the King
Kill the boss of the third castle
Reach the end of the level with the helicopter
Reach the end of the level with the watercraft
Kill the boss of the second castle
Reach the end of the level flying with balloons
Kill the boss of the first castle
Reach the end of the level with the skateboard