Capcom continues its diligent efforts to overhaul its arcade games for NES with a revamp every bit as admirable as Tecmo's fresh take on Rygar. A liner 1985 corridor shooter becomes a complex space labyrinth demanding patience, persistence, and a willingness to plot out some complicated connections, in effect becoming an all-new game—one diminished in history by its close proximity to Nintendo's Metroid and an unfortunate decision by Capcom USA to remove the save feature present in the Japanese release.