In Stacking, you're too small to do what you need to do. You can often be two or three people too small. To solve the game's puzzles, you're forced to assume the identities of some bigger people by donning their wooden skin. It sounds a little like a Castor Troy wet dream, but it's much sweeter than anything that fella thinks of when he goes to bed.
As a teeny little Russian nesting doll, you're able to stack inside anyone slightly bigger than you, who can in turn stack inside anyone bigger than them, and so on. It's the circle of life or something.
When you become one of these larger dolls, you're able to perform abilities specific to that character. There are dolls that can tap dance, dolls that can fart, dolls that can scream "MAKE WAY!" at those around them. And while some of you may think those three abilities would be enough to get through every day life, Stacking's puzzles require a little more thought.
A little more thought. Stacking isn't going to make your brain burst, and most of its challenges can be completed with relative ease, but the fact there are multiple solutions means there are loads of other dolls out there with quirky abilities for you to see. Every area is just bursting charm and full of characters that are beautifully designed. So, go on out there and start wearing the hand-painted shells of strangers. You'll have a lovely time.