In a land of impossible evils... all paths lead to the Dark Lord! A beautiful princess cries out in terror, and a world despairs in darkness. Only you, the hero warrior Victar, can traverse chasms of fire and mountains of doom to battle the fiendish gatekeeper and confront the Dark Lord. In your cunning and skillful hands, the Demon Sword grows with a magical power more lethal than all the wretched weapons of the Dark Lord's legions. Gather your courage, grasp your blade and release the power that is yours to control!
Demon Sword (不動明王伝, Fudō Myōō Den, "The Legend of Acala") is an action video game developed by TOSE and published by Taito in 1989 for the Nintendo Entertainment System. The caption on the box says to "Release the Power". This is consistent with the game's method of powering up the character's abilities.