Here is the full list of all 10 Gav-Gav Odyssey achievements.
Protect the dogs' waste
Complete the game on the difficulty of "Expert"
Face the masked monster
Release the dog named "Coal"
Collect 50 diodes in one run
Collect 20 diodes in one run
Release the dog named "Snowball"
Collide with spikes
Collide with a rocket on a spaceship
Collect 200 points on a spaceship