[Primer] Six Shades of Dressnought aka Vaka-Nought

[FTW]

Just got some Doorkeeper Thrulls, they should be nice in this build. Would they be good to replace perhaps, stifles?

Here are some good recent Thrull lists:
https://www.mtgtop8.com/event?e=54751&d=606932&f=LE
https://www.mtgtop8.com/event?e=54909&d=608230&f=LE

They all keep Stifle.