Since joining the Stars, Nill has dramatically re-shaped the team's culture and roster with a series of trades and acquisitions. He began to make his mark on the club with key acquisitions of centers Tyler Seguinand Jason Spezza and three-time Stanley Cup champion Patrick Sharp. After leading the team to regular-season Central Division and Western Conference championships in 2015-16, Nill was named a finalist for GM of the Year, marking his first career nomination. He'd continue to add more pieces over the next few seasons, including trading for goaltender Ben Bishop and signing right wing Alexander Radulov, goaltender Anton Khudobin and center Joe Pavelski, leading to a highlight season for the Stars in 2019-20. Following the NHL's pause due to the COVID-19 pandemic, the team traveled to the Edmonton bubble and advanced to the Stanley Cup Final for the first time since the 2000-01 season and the fifth time in franchise history, ultimately losing in six games to the Tampa Bay Lightning. Nill's accomplishments and roster building during the 2019-20 campaign was recognized, as he was named a finalist for GM of the Year for the second time in his career. He has also used the NHL Draft to build the core for both the team's present and future, selecting standout players such as Hintz (2015), Miro Heiskanen(2017), Oettinger (2017), Robertson (2017), Ty Dellandrea(2018), Thomas Harley(2019) and Wyatt Johnston(2021).