Mystic Defender is the USA version of the Japanese game "孔雀王２" (Kujaku-Oh Ni, which means "The Peacock King 2"). Except for changing the clothing of the hero and deleting the intro and the names of the stages, everything seems to be the same.
Because Peacock the hero is not a very smart hero, he cannot walk and use his arms at the same time (a common video game character disability). Thus he must jump to be able to use his arms. If he is charging a bigger shot when he lands, he forgets to walk for a few frames, so you cannot charge up a shot too early. It's all very delicate.
This is Highness' first published movie here.