Here is the full list of all 10 Ruthless Safari achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Runs 100 kilometers
Runs 85 kilometers
Runs 75 kilometers
Runs 65 kilometers
Runs 55 kilometers
Runs 45 kilometers
Runs 35 kilometers
Runs 25 kilometers
Runs 15 kilometers
Runs 5 kilometers