I've tried in the past to come up with themes that aren't stuck to a rigid image and i think i failed at that, so this time I wanted to bring something very open to the suggestions.

"Rings" there is a very wide range of things that this could mean, fighting ring, sonic style collectable rings, ring weapons, magic rings, halo rings etc.

and

"Doctor(verb or noun)" this could be medical, or manipulated, altered, changed, etc, lots and LOTS of open space here for interpretation, maybe too much.