Here is the full list of all 30 Defender's Quest: Valley of the Forgotten achievements.
Upgrade all the unique armor in new game+
Earn all the books from bonus challenges in new game+
Reach wave 100 on Endless Challenge 2 in new game+
Earn 201 Blue Stars
Earn 201 Gold Stars
Defeat the Super Sheep in new game+
Upgrade all the unique weapons in new game+
Level your Librarian up to LVL 60
Complete the game in new game+
Earn all the books from bonus challenges in the standard game
Reach wave 100 on Endless Challenge 2 in the standard game
Earn all the unique weapons in the standard game
Earn all the unique armor in the standard game
Beat all side quests in new game+
Level your Librarian up to LVL 40
Defeat the Super Sheep in the standard game
Level your Librarian up to LVL 25
Unlock a level 20 skill
Complete the standard game
Level your Librarian up to LVL 10
In battle, boost a character to the max boost level
Unlock all 6 character classes (not counting Librarian)
Beat any level on Extreme.
Use an advanced targeting option
Visit the tips menu (overworld->tips)
Visit the controls menu (options->controls)
Visit the accessibility menu (options->accessibility)
Beat the standard game without any generic recruits
Beat the game in new game+ without any generic recruits
Earn 180 gold stars without any generic recruits. For your sanity, we recommend increasing XP gains to 300% in the options menu!