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