[OP17-020] - Shanks (The World's Strongest Warriors)

If I have no cards in my hand, can I rest 1 of my DON!! cards with this [Activate: Main] effect?

Yes, you can. In this case, by resting 1 of your DON!! cards, you can apply the effect “Up to 1 of your opponent's rested Characters will not become active in your opponent's next Refresh Phase.”