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This stage is really nothing special. Attack the Blue Thieves for six magic pots, then continue onwards for a miniboss fight against General Heartland backed up by a Red Heninger and Red Longmoan. Since they're just stronger versions of their usual selves, take out the weaker ones first then concentrate on the giant. Don't use magic here as you need it for Death Adder himself, who is up next.

In the arcade, snakes slither together to form Death Adder. In most home versions he merely comes out of the double doors. Either way, this is a difficult battle. Use all your magic, then finish off the Skeletons. In the home versions there are two White Skeletons, while in the arcade there are four Purple Skeletons. You can now focus on Death Adder. He is much like Death Adder Junior from Beginner Mode. He has a habit of throwing out balls of moving fire if you get a certain distance from him. Jump over them if you can. Note that they pass harmlessly through enemies so you can't simply get behind a foe to escape them.

Death Adder is vulnerable when he crouches to throw his balls of fire--you can get a few hits in during this time. When he gets up he will often use an attack immediately, so try to stay clear.

Your character will walk over to one of the pillars and the King and Princess are lowered from the ceiling. In the arcade, they thank you and it's all over; you then get to see your Score. In the home versions, however, they tell you Death Adder may have been only the servant of some greater evil, and that he sometimes went through the big doors. You head on through them.