Here is the full list of all 30 So Many Me achievements.
Dream.Build.Play
Have 3 different Transmuter Fruits on 3 ME at the same time
Kill 10 Cloud-9 soldiers while both 9th Rifle and Helmet are turned on
Have a ninja hanging upside down on a blue fist
Turn on every light in Chrono Castle
Acquire 42 costumes
Reach 100% completion
Finish Chrono Castle XII without turning on Etherizer
Collect every coin in Chrono Castle
Score 50 or more in Chrono Castle XV
Finish the game
Acquire every ME
Unlock both gates at Volcano's entrance
Craft 10 artifacts
Score 80 or more in Chrono Castle XIV
Score 550 or more in Chrono Castle XIII
Finish Chrono Castle XI with both coin bubbles collected
Defeat the rival
Walk around the moon
Confront all possible questions in Chrono Castle X and choose all correct answers
Defeat a Duffon
Fail your friends
Have 8 ME in 8 different appearances at the same time
Finish any level while riding a Jellosaur
Meet Woodword
In the Chono Castle, Stomp on enemies' head 10 times, without falling down to the ground or creating stone block
Enter Chrono Castle
Rescue a girl
Use the Gene Splicer to create Jellosaur
Acquire the first ME