Rings provide the smallest surface area for contact in calisthenics. The most difficult elements on rings uses the least amount of connective tissue through the hands, arms, and shoulders for lifting and the most amount of primary, large, and core muscles for stabilization.
10
From a hang, straight arm pull to victorian cross
9
Zanetti, back lever to maltese
8
From arm rings support, press to either reverse planche, reverse straddle, handstand, or inverted cross without piking.
7
Standard grip, straight wrist, straight arm, rings turned out iron cross elements
6
From a hang, straight arm pull into reverse planche, reverse straddle, or manna/pike reverse planche, all done with straight wrists with rings turned out