It might not have to penetrate his skin. If it struck flesh (even if it bounced off) it would spread it's influence to him - remember how swiftly his mood changed upon holding the red K in Dr. Friskin's office. And it does make his powers go haywire - so it's not just something that affects him mentally.

Battle On,
Deadly Chakram

"Being with you is stronger than me alone." ~ Clark Kent

"One little spark of inspiration is at the heart of all creation." ~ Figment the Dragon