I'm stuck on the 4th mission where you have to fly low through canyons to draw out the evil dragons.

I have no clue where to go. I fly into the mountains, fail if I fly above them, and it seems like I've explored every bit of the inside canyons and can't find anything to trigger the rest of the mission. No ground targets and no flying enemies show up. The magic arrow never tells me where to go.

I also can't find a single guide for this game online, only the NES version. Every long play video on Youtube goes with the Order of the Sword, and since this mission is only with the 4th bronze dragon mission, it's never shown.

Anyone know what you're supposed to do in this mission?

Yeah, this mission is annoying, but it's all due to how easy it is to get lost. The lack of any map mechanic and the absence of the magic arrow can really make things confusing. There's actually a very straightforward route to take, but because the game never tells you where it is, you just kind of have to blunder onto it by accident.

Your target is a small enemy outpost. The only hint you have as to which direction you're supposed to fly in is an offhand mention in the mission briefing about heading east. When you begin the mission, maneuver your dragon around a little so that your compass direction (in the upper right of the screen) becomes highlighted. This is so you'll know which way you're pointed.

Begin by heading straight into the mountain pass located directly in front of you when the mission starts; your compass will show you heading south. At the first fork in the canyon you encounter, turn to the right. Your compass will briefly show you heading west, but the shape of the canyon will gradually nudge you back to the south.

At the next fork in the route, turn left. This will give you a compass heading of due east, which is the way you want to go. Keep flying straight for a minute; you'll know you're heading in the right direction because you'll be able to see the blue of the ocean on the horizon, and you'll fly over a number of small ridges in the pass, none of which will block your way.

When the "ocean" texture vanishes and is replaced by a mountain wall, look for an opening on your right. This will lead onto an open plain with your target located in the center. The outpost looks like a small tent; hit it with a lightning bolt to finish the mission.

This isn't the only successful route you can take, but it's certainly the most direct, and is probably the one the mission designers wanted players to use; on my first successful run, I flew over one of the higher ridges, followed the outside edge of the mountain, and came at the outpost from the other side. But really, it's just trial and error until you figure out where you need to go.