Here is the full list of all 22 Bardbarian achievements. It takes around 10-12 hours to unlock all of the achievements on Windows.
Complete the "noon" chapter.
Waltz into Wave 10 and rescue him from that Fire Golem.
Upgrade a unit to MAX level.
Loot 100,000 gold from the corpses of your fallen enemies.
Fact: There are 1609 meters in a mile.
Start a new game in Insane Mode.
Don't get hit!
Last for 3 minutes in survival mode.
Play and submit your best time for Survival Mode.
Appears randomly in Survival mode. May luck be with you.
Reach 3000m in Escape mode, and he's yours.
Complete the "morning" chapter.
You look lonely, have you considered a pet to keep you company?
Something's cooking on the title screen.
Complete the "evening" chapter.
Complete the "night" chapter.
Send 2500 enemies to their grave.
Go as fast as you possibly can. (Hint: Upgrade + Song)
Complete the entire campaign from start to finish without dying.
Do all the things! 100% Completion.
Unlock the mythical 4th party slot.
Post a score in the Day 2 Insane Mode leaderboard. The most exclusive of all leaderboards.