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 "evening" chapter.
Loot 100,000 gold from the corpses of your fallen enemies.
Something's cooking on the title screen.
Complete the "noon" chapter.
Upgrade a unit to MAX level.
Waltz into Wave 10 and rescue him from that Fire Golem.
Send 2500 enemies to their grave.
Reach 3000m in Escape mode, and he's yours.
Last for 3 minutes in survival mode.
Appears randomly in Survival mode. May luck be with you.
Play and submit your best time for Survival Mode.
Don't get hit!
You look lonely, have you considered a pet to keep you company?
Complete the "morning" chapter.
Complete the "night" chapter.
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.
Start a new game in Insane Mode.
Fact: There are 1609 meters in a mile.
Post a score in the Day 2 Insane Mode leaderboard. The most exclusive of all leaderboards.