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