The Robotnicus is Dr. Robotnik's personal luxury airship. In the Issue 47 story Captain Plunder & His Sky Pirates Part 1, the doctor was throwing a party for his many evil allies and colleagues to celebrate his birthday until the ship was attacked by Captain Plunder and his crew, who had come to raid the ship's vault (which could only be opened with two keys, one of which was at Robotnik's destination, the other at a fortress) containing treasures taken from the citizens as taxes. Despite nobody apparently knowing about the secret party, Plunder's heist was successful and his crew got away with the goods. However, the captain himself was captured and transported to the Metropolis Zone where he would begin his trial on charges of treason.