I'm being generous here, because the free draggables make things too easy. For a challenge I decided to "catch" one of them as they fell at the opening and drag it over the win, but even that turned out to be easier than I thought. So my only question is ... Spoiler did you intend for me to use a free draggable to assist B in reaching the win? If so, there is more than 1 way to do it.
@Woussif You could have achieved the same opening decoration using balls or motors. No way players can use those as cheats. Spoiler: Example card
