Single Leg Glute & Hamstring Triset
Most leg workouts, if they happen at all, put a lot of focus on the muscles of the quads with movements like squats, leg presses, and leg extensions, but the hamstrings and glutes are an afterthought, maybe getting a few sets of leg curls at the end of a workout.
This circuit turns everything on its head, putting all of the stress on the glutes and hamstrings and removing the lower back from being a significant factor by keeping the stress on one leg at a time.