Here is the full list of all 12 The Defenders: The Second Wave achievements.
Parried 50 enemy projectiles
Have used over 3500 mana
50 kills without taking damage
Killed at least 1000 enemies
Tanked 1000 hit points without dying
Started a game
Unlocked trial mode, because the game is so good =)
Killed at least ten butterflies
Struck the moon
Won the game on "Easy" difficulty
Won the game on Normal difficulty
Won the game on Hard difficulty