IMPuzzeled

IMPuzzled uses the OpenType feature of Contextual Alternatives to alternate two sets of characters. The sets are on two puzzle pieces that tessellate, that is, fit together to fill the plane with no gaps or overlaps. Empty pieces are on the brace keys and can be used to fill spaces. The black or solid style is designed to be used in a layer under the regular style, though it can be used alone if adjacent pieces are given different colors.