Here is the full list of all 14 Boneless Zombie achievements.
Can zombies even die? (Die by a method other than self-destruct.)
Don’t forget to stretch. (Get real, he’s got no bones.) (Stretch his arms and legs a total of 100 times.)
The first step in a great escape story! (Clear Stage 1.)
This is his lifeline. (Get “life pod.”)
Why is the self-destruct switch... (Use self-destruct.)
Did he have them to begin with? (Get “bone.”)
Even if he can’t walk. (Roll to move.)
He picked up scattered bones. (Acquire all the bones in 5 stages.)
Head through the goal together. (Clear a stage while holding onto a trolley.)
He can play ball, too. (Put a ball through the goal.)
Score one for the enemy! (Go through the goal while holding the ball.)
He’ll rise again as often as it takes. (Retry 50 times.)
The conclusion of the great escape? (Clear the final stage.)
He remembered his name. (Acquire all the bones in all the stages.)