Zug is an ambitious young tug, and one of the Z Stacks switchers. He mainly works with Zip, and likes to think of himself as the intelligent one. Compared to Zip, he certainly is intelligent. Compared to anyone else, he's not. He comes up with devious plans for him and Zip to use, though the plans usually fail. Zug is Captain Zero's 4th Tug, a harbour switcher who is used for a wide variety of tasks around Bigg City Port.
- His design is loosely based on the Moran Fleet of NYC waters from the 1920's.
- Zug is voiced by British actor Mike Mulloy who voices Captain Zero and Izzy Gomez.
- In the American TUGS Spin-off Salty's Lighthouse, He turns good and he was first voiced by Scott McNeil and later Kirby Morrow.
- In the Japanese version he was voiced by Taro Arakawa.
- Like Doctor N.Gin from Crash Bandicoot, Zug's accent is reminiscent of the late actor Peter Lorre.