A Sandbox Ceasar is business person, usually in middle management, who was bullied as a child (in the sandbox) and has to make up for it as an adult by being a rude, power-mad, greedy asshole. Will walk over anyone to prove they can't be picked on anymore. They want to be as powerful as Julius Caesar, which is why they act like total douchetards.
"Did you hear Christine going off in that meeting? She was backstabbing everybody to make herself look good."
"Yes, she's a total Sandbox Caesar. I hate her."