Here is the full list of all 33 Runner3 achievements.
Unlock EVERYTHING!
Buy a bunch of new digs!
Get all your friends over for some GRILLINS!
Collect all the Narrator's Puppetshow Puppets!
Finish all 9 Impossible Levels!
Witness something creepy.
Get a Special in each Standard Level in any World!
Get all the Gildans!
Defeat the Jungle Ruins' Boss!
Go exploring in the Retro World. Maybe you'll find a cute secret?
Bonk the Timbletot!
Defeat Machineland's Boss!
Got 'em All!
Invite a friend to the BBQ!
Defeat The Caves' Bosses!
Defeat Spookyland's Bosses!
Buy a bunch of Capes!
Defeat Foodland's Boss!
Get a Perfect in each Standard Level in any World!
Better out than in...
Buy a bunch of Accessories!
Head off the Beaten Path...
Make it to the end of an Impossible Level!
Collect all Golds and Gems and finish an Impossible Level!
Defeat The Great Outdoors' Boss!
Checkpoints? Who needs 'em!
Get a Perfect+!
Get a Special+ and a Perfect+ in any Level!
Get a Special!
Get a Special+!
Get a Special AND a Perfect in any one level!
Get a Special, a Perfect, and one Bullseye in any Level!
Get a Perfect!