This massive robot is formed out of many smaller Grundo bots. Sophix II used it against the resistance during Sloth's invasion, forming part of Wave 3. It was eventually dismantled by the resistance.
YOU WILL NOT DESTROY US!
ATTACK!
Something smells like it is burning...
Give in to my master and save yourself.
This will not end well for you.
The resistance will fail.
Dr. Sloth will not tolerate failure.
That isn't a very good attack.
That must have hurt...
You will not move now.
NOOOOO!!! You will pay for that!
You will never defeat sloths forces!