Pattern for the lost foam casting process including a pouring-basin-foming portion, a sprue-forming portion, a runner-forming portion, a gate-forming portion, and a riser-forming portion. The sprue-forming portion forms an inverted conical sprue having a blade-lightener therein for quickly filling, and substantially simultaneously firing, the gates. A glue joint may be used between the pouring- basin-forming portion and the sprue-forming portion to increase the residence time of the melt in the pouring basin. The runners formed by the pattern each have an inline riser through which melt flows during pouring and in which melt is stored to feed the casting with melt during shrinkage of the casting A sand dam surrounds the mouth of each gate and traps particulates from a liquid styrene layer that precedes the melt front in the riser.