Here is the full list of all 28 FrostRunner achievements. It takes around 1-2 hours to unlock all of the achievements on Windows.
View the Credits
Get the Gun
Get the fast time on all levels
Obtain all collectibles
Collect the Sword
Collect the Frog
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Obtain 20 unique collectibles
Obtain 10 unique collectibles
Finished Chapter 5 - Chain
Get the fast time on all levels in Chapter 5 - Chain
Finished Chapter 4 - Fling
Get the fast time on all levels in Chapter 4 - Fling
Finished Chapter 3 - Tether
Get the fast time on all levels in Chapter 3 - Tether
Used fling for the first time
Tethered for the first time
Finished Chapter 2 - Ice
Get the fast time on all levels in Chapter 2 - Ice
Finished Chapter 1 - Ring
Get the fast time on all levels in Chapter 1 - Ring
Died for the first time
Finished the Prologue
Get the fast time on all Prologue levels
Found a collectible
Obtain an achievement...see what we did there?
Took your first steps
Jumped for the first time - Feel proud!