Balance is the game in puzzle genre. The point of the game is that figures of familiar form falling from two sides. The player's challenge is to place figures in center of field the way that would keep balance between two different zones. The player looses if one of the field sides reaches the opposite edge.
Falling pieces becomes a part of the opposite field.
Use simple parts to create complex structures.
You do not create a straight lines, but trying to offset changes for each side what makes you think differently.