Castle magic can make items translucent, opaque, and invisible. Make a castle magic card that can remove an item’s borders, while still being visible. With the item's borders being removed, players can see the item but they can also walk inside and through it.
A castle magic card that makes an item invisible, while keeping its borders would also be cool. With the item invisible but its item's borders still in place, a player can't see the item but they will still be stopped by the item's borders. Invisible wall castle blocks won't always work well; sometimes the area a wizard wants bordered can be a specific shape or size; a size that is meant to be a similar or an exact size of the visible version of the object.
