KirriCorp

If u damage ur opponent with ur snowball while the opponent has no creature/rune in conflict, the opponent cannot choose a target (obviously), nor cancel the choice. The duel gets stuck and the only option is to forfeit or leave the duel incomplete.

Please look into the issue as soon as possible.

I tot forfeit is more good than leaving it and maybe if your oppnent got none creater to choose to give snowball effect it count as lose so your opponent needs to surrendder !