|Japanese Name||Shinichi Kutsukake (沓掛真)|
|Age|| 35 (Under the Knife and Second Opinion)|
38 (Under the Knife 2)
|Family|| Sidney Kasal (younger brother)|
Cybil Myers (spouse)
|Friends|| Derek Stiles|
Dr. Greg Kasal's surgical skill, coolness under pressure, and reliability earned him a position as Hope Hospital's Senior Surgeon. He's the manager of the office for all intents and purposes, and is a kind person. However, he takes his job very seriously, and expects others to do the same. He is the first to be infected with the fourth strain of GUILT, Tetarti. He is the identical twin brother to Sidney Kasal.
- Trauma Center: Under the Knife 2: Supporting Character
A man in his thirties, he has slicked-back brown hair with a goatee and hazel eyes. He wears a lab coat over a beige dress shirt and wears a green tie with yellow and black stripes.
In Under the Knife 2, he changed his appearance, changing his usual get-up to a brown suit.
Under the Knife/ Second Opinion
Under the Knife 2
In Under the Knife 2, Greg is married to Cybil Myers and they have a baby daughter named Kari.