Hollow Fly

Guide your character through labyrinthine levels using the d-pad. Collect all the keys in a level to access the portal to the next stage. Avoid enemies and hazards that can lower your health. Fire your sonar beam to overcome enemies blocking your path. Look out for power-ups to increase your velocity, damage output, or HP. Note that losing a life will strip all collected power-ups. Advance through a trio of worlds, each with its own difficulties. Learn the layout of each level to progress more efficiently.