Here is the full list of all 14 Mekabolt achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Get 48 batteries
Meet the flying robot with a spike
Find a flamethrower
Unlock caves
Meet the wind maker robot
Meet the cactus
Get 24 batteries
Meet the bomb dropper robot
Meet the spear throwing robot
Unlock desert
Get 12 batteries
Meet the shooter robot
Meet the robot to jump
Meet the Flying Robot