Dean ambrose new name
You're referring to the former WWE superstar Dean Ambrose!
Dean Ambrose, whose real name is Jonathan Good, left WWE in 2019 and signed with All Elite Wrestling (AEW) in May 2019. He made his debut in AEW under a new ring name: Jon Moxley.
Moxley has been a key player in AEW, competing in various matches and feuds, including a highly acclaimed match against Kenny Omega at AEW's Full Gear pay-per-view event in November 2019. He has also become known for his intense and hard-hitting in-ring style, as well as his charismatic promos and interviews.
So, to answer your question, Dean Ambrose's new name is indeed Jon Moxley!