One time when I was lifting with my buddies on a leg day we did the following and I never want to do it again,my legs collapsed several times the following days and they were sore a hour after I left the gym. There was 3 of us so we would work as a team for every work out;
-Hack squats,1 person lifting,1 person on each side ready to pull a plate as needed. They loaded up 4 plates on each side,I would do that as many times as I could then say 'plate' and they removed one plate from each side then I continued until I couldn't do 3 plates and then I said 'plate' and would do as many as I could with 2 plates on each side. Try that for 4 sets.
-Leg presses,same thing,1 person on each side,we loaded up 6 plates on each side and worked out way down to 3 plates. Again for 4 sets.
-Dumbbell deadlifts,this was easy,it kind of like an intermission. Again 4 sets.
-Modified Dumbbells Squats,really hard to explain so I will skip this,but put it this way,until this day my legs still give after every set of these. 5 sets.
-Leg Curls,don't laugh these things are hell after a HARD a55 work out. 3 sets.
I remember it perfectly cause my lifting buddies were laughing cause my leg gave out when I went to go upstairs for a drink of water and I was in sooo sore for the next week. Normally we wouldn't go balls to the walls like that but my buddy is prepping for his contest and he feels his legs are behind so he's pushing it.