Discuss the routine Arnold posted to reddit a few days ago:

50 Pushups
50 Dips between chairs
50 Row between chairs
100 Sit-ups
50 Bent-leg raises
50 Bent-over twists
50-70 Knee bends (squats)
50 Calf raises
30 Chin-ups

I think he says to do the reps in whatever combination of sets/rest you want. The numbers are the "advanced" targets.

Can this build muscle? Or at least until we get out of quarantine? What can this achieve?