Golden Axe/Stage 4
Head forwards and immediately jump up onto the high ground. A Red Heninger and two Red Longmoans will appear from behind. Since you're on the high ground they'll try to jump up, meaning you can knock them out of the air. If they manage to make it onto the platform a simple combo will send them back to the ground. If you walk to the very bottom of this ledge they may walk off the small gap and fall into the water.
A Skeleton now appears from behind. Since there's only one of him he shouldn't be too much of a worry. Next, take the two magic pots from the Blue Thief. The sun will now set, indicating a boss fight.
First you'll face two Dark Longmoans and a Dark Heninger. They're only a bit stronger than the gold enemies from the previous level. Try to avoid them pinning you between them.
After this you'll fight a Skeleton and another Dark Heninger. Use the tactics from before. Next, two Skeletons and a Dark Longmoan appear. This is an even more difficult battle. You can use magic here if you wish (this is the final battle of this stage) or you can just try your luck avoiding them and using combos and jump- or dash-attacks.
 Bonus Stage
A piece of meat and three magic pots await you. This is the final Bonus Stage, so after this you shouldn't use your magic so freely as you have to get all pots from the stages themselves.
You discover the "Fiend's Path" was a giant eagle; it carries you to Death Adder's castle.