The Windmill Maze
First, start this level by shooting the generator in front of you to stop enemies from coming out, and collect the two treasures along with a key and three red crystals. Going up the hill, there is another generator along with a chest that contains a potion in front of an entrance to a maze. Note that once you get up to the third generator next to a red crystal in the maze, you cannot return back to the start of the level as the gates will block you from returning. Make sure you get the crystals and treasure prior to entering the maze.
Upon going a bit into the maze, there is a potion inside of a barrel near two other empty barrels. On the left is a path with a green barrel, which is toxic and will eat away your health unless you have a Gas Mask, so it is best to go on the other path. At the windmill ahead, there is another potion sitting in the corner. There is a generator in front of it, so make sure you don't accidentally hit it, or else it will explode and be a waste. Also, be careful near the windmill as you can take damage from the blades. On the opposite side of the windmill is a health item inside of a barrel. Continue on and collect the two red crystals and the health item on the same path to leave the maze. In the river area, collect the red crystal in a corner before moving on. When you get to the river area, go near the most bottom right of the area to find a generator near a barrel with a keyring inside. Go back up and get the two red crystals while avoiding the poison fruit in the middle. To the right of the poison fruit is a chest that contains a turbo boost. Above the poison fruit is a hidden wall with a chest that has a potion inside. Nearby, there is a hint scroll with a haystack that can be destroyed, which contains a red crystal.
The Guarded Vault
The first hint scroll of the game mentions a guarded vault, which is very close. Destroy the generator past the scroll if you haven't already and go up the elevator. At the top, there is a chest that contains acid breath. Go down the ramp to enter the area below and destroy the generator at the bottom. There is also an apple in the corner underneath the ramp if you are low on health. Nearby, there is a general and another generator near the vault that the scroll mentioned earlier. Kill the general and open up the vault to obtain the first runestone.
Go forward to the water wheel area and collect the five red crystals here and a key in a barrel behind a generator. Go up the ramp and collect the red crystals while watching out for traps on the floor. The chest above has meat in it, so get it if need and go down the elevator.
In the next area, turn around and hit the wall behind you to get the wings that elevate you and a yellow crystal. Now collect the gas mask above the elevator in a barrel along with two health items below. In this area, there are ankle biters, which are more of a nuisance than harm. Deal with the ankle biters and then go all the way bottom left to find a chest with a Phoenix Familiar inside.
On the way back, hit the haystack to get a keyring. Back up top, there are some red crystals and more ankle biters. There is another haystack nearby, which contains a blue and purple crystal. Below, at the bottom of the wall, there is another purple crystal, so collect them before moving on to the next area as well as the two health items to the left. Go past the haystack and get the purple crystal and open the barrel to get a keyring. Go around to collect four red crystals in the area. On the bridge, collect the health item in the middle and watch out for archers and bombers. The chest to the left contains a potion. Now go to the right of the chest to the opening in the bridge's side to raise a wooden log up to you that has a health item on it. Take it down to collect the two crystals below, and move forward to raise another two wooden platforms up with a Super Shot. Continue forward and around to collect four red crystals and hit the hidden wall below to get two treasures and a blue crystal. Go up and left to the next area, which is blocked by two red explosive barrels. Destroy them from a distance and continue on while destroying generators and killing grunts.
Up ahead is what appears to look like a sundial switch next to some health items. Collect the three health items if you need them, and get the purple crystal above the switch. Now hit the switch and go below near the river and the chest will have a treasure in it. Hit the switch under it to raise the sundial switch to reveal the first golden item. Collect it and move on to the next area. Now go up and up the ramp, getting the health item and hitting some boxes to uncover another health item. Be careful going on as there is a suicide grunt with a toxic barrel. In the same area, there is a chest blocked by a create that contains a Rapid Fire. Now go around and collect the health item inside of a crate and hit the switch behind you and get on the moving platform and collect the four crystals after getting off. You can shoot enemies from here as well as in other areas in the game, so take advantage of these times to get free hits.
In the next windmill area down below, avoid the green toxic barrels. Go to the right and collect the purple crystal in the corner and go up to collect the keyring along with the second hint scroll.
Go up the hill collecting two health items and three red crystals while avoiding the flame trap. In the next area, collect the meat that sits freely to the left and a health item in the barrel. One of the barrels has poison fruit in it, so avoid that. Nearby, there is a chest sitting next to a barrel. Remember what the scroll said? The chest has a trap that destroys items around it, so be careful as it takes health too when you get hit by it. Be sure to get the health item in the barrel instead of opening the chest, otherwise you lose out on free health. Open the gate above, ride the elevator above and avoid the traps on the walls.
In the next area, collect the potion in the middle and hit the switch above you to lower the bridge to the general above. Now go right and destroy the generator while collecting the key. Above is a chest with a barrel behind it. Where have we seen this before? Just like the scroll mentioned and just like the previous trap, it's the same trap yet again. Walk behind to where the switch and key is and open up the barrel, which contains meat. Now grab the key and hit the switch in the corner to lower a platform in front of the exit. The barrel next to the key gate is another hint scroll.
As the hint scroll mentions, you need two switches in order to exit the level. They are both in the same area and should have already been used by the time you even get to the scroll. Open up the gate and go up the hill to collect four red crystals while avoiding another flame trap. There is a barrel near the bridge with contains a turbo powerup along with a general to kill. Once the general is killed, walk across the bridge and be careful of another suicide grunt waiting for you on the opposite side of the bridge.
Moving left and around to the next area, there is another hint scroll next to a generator.
Just like the hint says, nearby there is a stationed red death guarding the exit switch. Conveniently, there is also a potion nearby to deal with this death, provided it wasn't destroyed by the red barrel or one of your attacks. You can actually walk past the red death and collect the purple crystal/hit the switch to lower the gate, though it will immediately activate and follow you, which is bad if you don't have a potion as that cliff is essentially a dead end. If you have a potion, deal with the death. If you don't have a potion, activate the death before pressing the switch, and get it stuck somewhere so you can safely press the switch without getting your health drained. Near the exit, there is also a barrel, but it only contains poison fruit.
Once the gate is lowered and whether or not the death is taken care of, you are free to exit with a blue crystal to collect for your troubles.