Alex Kidd in Miracle World DX

***Need to be done with infinite lives off***

You can easily achieve it through stage select after beat the game for the first time, even if using infinite lives.

This is the boss in the end of Namui Village stage. You will pass through a mistery box [?] before it, if you have accessed it through lvl select, just smash the box to get the ring and equip it when reach the red balls, then you just need avoid the bull's charge and shoot fire balls on him from his back before he start his next charge.

Tip: The [?] box gift you with a ring, a ghost that kills you and an extra life. ALWAYS at this order. So, if you have got a ring in the previous box you smashed, the next box will be the ghost. If you got a life, you'll get a ring.
This happens even when you die and break the same box again. Then take care with it to make your life easy facing bosses.