Here is the full list of all 39 Death end re;Quest 2 achievements.
Completed all story endings and explored all paths.
Viewed the EX Ending.
Defeated Ao Oni in the Pain Area.
Defeated 1000 enemies.
Viewed most of the main story.
Played the Ao Oni mini-game.
Viewed the True Ending.
Defeated the final boss.
Viewed the Fallen Ending.
Cleared Chapter 10.
Learned 15 of Al's skills.
Cleared Chapter 9.
Cleared Chapter 8.
Learned 15 of Lily's skills.
Used Glitch Mode a great many times.
Viewed many story events.
Viewed all of the Death Ends.
Cleared Chapter 7.
Learned 15 of Clea's skills.
Learned 15 of Celica's skills.
Learned 15 of Shina's skills.
Cleared Chapter 6.
Learned 15 of Lucil's skills.
Used Glitch Mode a handful of times.
Cleared Chapter 5.
Cleared Chapter 4.
Learned 15 of Liliana's skills.
Cleared Chapter 3.
Learned 15 of Rottie's skills.
Learned 15 of Mai's skills.
Entered Glitch Mode for the first time.
Activated Super Knockback for the first time and sent the enemy flying.
Cleared Chapter 2.
Viewed most of the sub-events with your classmates.
Activated Knock Blow for the first time.
Cleared Chapter 1.
Used a Flash Drive skill for the first time.
Activated Knockback for the first time and sent an enemy back.
Entered Camp for the first time.