Here is the full list of all 26 BIT.TRIP RUNNER achievements.
Complete a level in one sitting
Get the Game Over
Watch the hidden cutscene
Complete Triumph
BURGER MOUTH
Complete The Gauntlet
Find 3 friends and beat the challenges they are in
Get Bonked by a monster
Repel 100 Beats
Complete Tenacity
Catch a fish!
Get a PERFECT on one challenge
Complete Impetus
Complete Odyssey
Collect 1,000 Gold Bars
Jump 1,000 times
Bonk after missing a Gold Bar to rewind time and try again
Roast your mallows over a campfire
Register a high score on the leaderboards
Complete a bonus challenge
Get CommanderVideo's cape
Get a PERFECT score in all Impetus Challenges
Get a PERFECT score in all Tenacity Challenges
Get a PERFECT score in all Triumph Challenges
Get a PERFECT in all challenges
Beat all challenges on Perfect difficulty