Here is the full list of all 22 Etrian Odyssey HD achievements.
Defeated an Yggdrasil Bud, Yggdrasil Sprout, and Yggdrasil Clover.
Obtained more than 250,000 Ental.
Defeated the Dragon.
Defeated the Drake.
Retired an adventurer.
Let an adventurer rest.
Defeated the Wyrm.
Defeated a boss in a single turn.
Reached the Sixth Stratum.
Defeated the Etreant.
Dealt 1,000 damage with a single hit.
Reached the Fifth Stratum.
Unlocked the Hexer class.
Reached the Fourth Stratum.
Completed the quest "The bandit's treasure".
Unlocked the Ronin class.
Reached the Third Stratum.
Reached the Second Stratum.
Reached the First Stratum.
Obtained all other achievements.
Defeated the boss of the Sixth Stratum on Expert difficulty.
Defeated the Yggdrasil Core.