How do I kill the Vendinator
Every time its energy is almost depleted, it regain it full again.
Apparently only shooting it doesn't work.
Is there something else I have to do to kill it?
You keep shooting it and it will change the color of the status bar indicating that it became less powerful.
When it becomes red, the pillars on the side will become targets with hitpoints. Shoot them and then focus on Vendinator.
Now it will die permanently.