Here is the full list of all 24 Mirt. Tales of the Cold Land achievements.
Collect all the diary pages
Stay in the Campus
Open your Eyes
Get All the Endings
True Ending
Choose the Dark Side
Choose Oblivion
Sacrifice Yourself
Trust Taro
Lose Veronika
Save Veronika
Meet Paul
Break up a couple
Don't Escape
Betray Taro
Choose the Present
Choose the Future
Read by Shadows
Save Grin
Complete Chapter 2
Stay out of the way
Complete Chapter 1
Collect all the pages in Chapter 1
Visit the Moon Cafe