A system for forming a shoe (100, 402, 702, 802) comprising; a perforated last (302, 502, 602, 1002); a mold (404, 506) with a cavity (408, 504) shaped to receive a bottom region of the perforated last (302, 502, 602, 1002); and an injection machine configured to couple to an inlet port (414, 518) in the mold (404, 506) and to inject a material configured to foam and form a sole (104, 214), wherein the perforated last (302, 502, 602, 1002) has a plurality of perforations (308, 508, 610, 1006, 1012) extending through a thickness of a wall of the perforated last (302, 502, 602, 1002), the plurality of perforations (308, 508, 610, 1006, 1012) fluidly coupling air inside an inner conduit (312, 514, 604) of the perforated last (302, 502, 602, 1002) to air outside of the perforated last (302, 502, 602, 1002) and wherein the plurality of perforations (308, 508, 610, 1006, 1012) are clustered adjacent to regions of the midsole (112, 216, 424, 712, 812) where an increased thickness of the sole (104, 214) is desired, and wherein the perforated last (302, 502, 602, 1002) is substantially solid and the inner conduit (312, 514, 604) extends down from an opening at a top of the perforated last (302, 502, 602, 1002) through a portion of a height of the perforated last (302, 502, 602, 1002); wherein a manifold is arranged within the perforated last (302, 502, 602, 1002) and is coupled to the inner conduit (312, 514, 604), wherein the manifold is fluidly coupled to the inner conduit (312, 514, 604) and extends through the perforated last (302, 502, 602, 1002), wherein a portion of the perforations (308, 508, 610, 1006, 1012) are fluidly coupled to the manifold, thereby fluidly coupling air surrounding the perforated last (302, 502, 602, 1002) to air inside the inner conduit (312, 514, 604). a perforated last (302, 502, 602, 1002); a mold (404, 506) with a cavity (408, 504) shaped to receive a bottom region of the perforated last (302, 502, 602, 1002); and an injection machine configured to couple to an inlet port (414, 518) in the mold (404, 506) and to inject a material configured to foam and form a sole (104, 214), wherein the perforated last (302, 502, 602, 1002) has a plurality of perforations (308, 508, 610, 1006, 1012) extending through a thickness of a wall of the perforated last (302, 502, 602, 1002), the plurality of perforations (308, 508, 610, 1006, 1012) fluidly coupling air inside an inner conduit (312, 514, 604) of the perforated last (302, 502, 602, 1002) to air outside of the perforated last (302, 502, 602, 1002) and wherein the plurality of perforations (308, 508, 610, 1006, 1012) are clustered adjacent to regions of the midsole (112, 216, 424, 712, 812) where an increased thickness of the sole (104, 214) is desired, and wherein the perforated last (302, 502, 602, 1002) is substantially solid and the inner conduit (312, 514, 604) extends down from an opening at a top of the perforated last (302, 502, 602, 1002) through a portion of a height of the perforated last (302, 502, 602, 1002); wherein a manifold is arranged within the perforated last (302, 502, 602, 1002) and is coupled to the inner conduit (312, 514, 604), wherein the manifold is fluidly coupled to the inner conduit (312, 514, 604) and extends through the perforated last (302, 502, 602, 1002), wherein a portion of the perforations (308, 508, 610, 1006, 1012) are fluidly coupled to the manifold, thereby fluidly coupling air surrounding the perforated last (302, 502, 602, 1002) to air inside the inner conduit (312, 514, 604).