Democrats or Republicans get gifted a 535-0 majority in Congress. What happens?

Only half-jokingly:

D’s: Would get embroiled in internal bickering between the more militant progressives and more moderate factions; in the end, would get nothing done. Also, Bernie Sanders gets hit in the face with a tomato thrown by Kyrsten Sinema right in the Senate chamber.

R’s: Would get a lot done, all of it wrong and stupid, sending America to hell in a handbasket. Would also set standards for “free and fair elections” which, remarkably, guarantee that Republicans keep getting re-elected forever. Also, there is a $500,000 minimum annual income requirement for white voters, and Blacks can no longer vote at all.