IDP fantasy managers get a concise guide to 2025 sleepers, breakouts, and busts across four-defender formats. Edgerrin Cooper’s late-season surge for Green Bay signals breakout potential, while Nik Bonitto’s spike season in Denver makes him a prime breakout candidate at a discounted price. Cooper DeJean’s versatility with Philadelphia hints at a high-ceiling role, and Jalon Walker’s athletic potential makes him worth late-round risk in redraft formats. The article also highlights deep sleepers like Marques Sigle, Mike Green, Dee Winters and Jack Kiser, plus notable busts such as DaRon Bland, Bradley Chubb, and Nakobe Dean, emphasizing ADP context and format variability across IDP leagues.