Here is the full list of all 15 Slinki achievements.
Beat the game on Normal Mode.
Beat the game on Hardcore Mode.
Collected all easter eggs.
Made a Beartoise commit suicide.
Defeated Mr. Owl without taking damage.
Went between the legs of a Beartoise.
Just letting you know...
Ignored the level designer's suggestion.
No really, it's ok.
Spun the wheel and owned the competition.
Denied a kamikaze's noble sacrifice.
Beat the game, on any mode, without dying.
Someone had to cut it...
Sanic "The hodge" Hodge won't spin again
Didn't panic because of the falling Hodges.