Raijin is a green Djinn-like creature that appears in the first stage where it acts as the boss. Raijin floats around the screen and launch lightning bolts at the player.
In order to defeat him, the player has to throw items at him. One single item would be enough to defeat him, but Raijin has also the ability to use a shield to protect himself against the items thrown by the player, making the battle more difficult.
This boss can be skipped if the player just keep walking, but the player won't get the bonus points for defeating the boss.