Here in this swamp map you must collect three Fire Masks and then press three switches in areas each Fire Mask allows you to activate, in order to claim the map's planet gem.
Note the pillar you place the Fire Masks in to your left when you start and the three slime rivers.
You must collect the Fire Masks in a specific order. However you can place each one in any of the three slots and hence press the three switches in any order. Hence the layout of this article.
Fire Mask 1
This can be found south from your position. Head around the central structure keeping an eye out for Slaughtaurs firing from the moving platforms around the sides. Which ever way around the central structure you go, you will pass one of the other two Fire Masks behind bars.
There is an entrance south of the structure leading to a mountain of slime and Stalkers. The first Fire Mask is on top of it. Naturally, you have to jump into the slime around the mountain and then climb it.
Fire Mask 2
Once you have pressed the switch at the end of the area beyond the slime river you lowered with the first mask, the previously locked door to the left of the slime mountain, where you found the first mask, will open. Behind it is a long passage way that snakes around to the back of the left Fire Mask containing cage; though watch out for the moving pillars as they will crush you if you get caught in between them.
On the way down the passage, you'll also be able to jump onto the backs of the left Slaughtaur carrying moving platforms. Clerics will be able to find the third segment of their fourth weapon on one of these platforms.
Fire Mask 3
Once you have pressed the switches at the end of two of the areas beyond the slime rivers you lowered with the first and second masks, the locked door on the right of the slime river will open revealing a passage way similar to the one that led to Fire Mask 2.
One of the platforms here has the Fighters second segment of their fourth weapon.
Again watch out for the moving pillars on this side, and the crusher right in front of the Fire Mask. Once you pick up this Fire Mask, a pen revealing a few Slaughtaurs will open further back down the passage. Inside the pen is a teleporter that will take you to a small room containing an Icon of the Defender.
Beyond the Slime Rivers
Each of the three slots where you place a Fire Mask will lower a different slime river, leading to a different challenge and one of the three switches you must press to be able to access the maps gem.
Warning: Note that Stalkers respawn in groups of three at intervals while you are on the level, and the slime rivers you play later will be nearly full of them, making simply entering these areas the most dangerous parts of the level. Trying to kill them in the trench will most likely get you swarmed and killed; rather, it may be a better option to run down to the pools and kill them in the more open area.
North Slime River
Note that the Cleric's third weapon is available down this river, so Cleric players may wish to lower this one first.
After jumping down and dealing with all the Stalkers lurking around. Note the teleporter in the top right, which will return you back to the start area.
Enter one of the two openings at the other end of the pool to enter a circular corridor. However rather than go all the way around it, you want to turn toward the other opening where you will find a Chaos Serpent. (If you used a "kill all" cheat, the Serpent will not be there and the central area thus permanently closed.) Slay it and a wall around the inner side of the corridor will lower unleashing several bad guys and also another Chaos Serpent. Slay this one and another wall will lower around the inner side of the corridor. Repeat this several times and the entire centre will have lowered turning the area into a large open room, though you may want to circle around the corridor each time to pick off the other bad guys before slaying each serpent.
When you slay one of the serpents lowered on the final lowering wall, another wall will lower at the back of the room, containing the switch, which will open the passage to the next Fire Mask and also lower the pillars of slime back outside, unleashing more Chaos Serpents. Your only aim now is to get to the afore mentioned teleporter.
East Slime River
Jump down and deal with the Stalkers. This is the only river where an exit teleporter isn't provided until you press the switch.
Fortunately this is a quick switch to reach. Enter the circular room behind the pool and follow the walkway around to the other side, making sure not to fall in the lava, as at this stage there is no way out, to find the switch. Pressing it will open the passage to the next Fire Mask and lower the star in the middle of the lava pool, in the middle of which is the teleport that will take you back to the start of the map.
West Slime River
Kill the Stalkers down in the pool and enter the narrow passage over the other side of the pool to enter a maze of moving slime platforms, bottomless pits and of course more than a few Stalkers.
There isn't really much guidance to give here except to note that you must work your way toward the north west corner of the maze. Though you might want to travel the south east and west sides of the maze to find a few Quartz Flasks and a Mystic Urn respectively.
Once you reach the north west corner of the maze you will come across a small room with several steel pillars and more Stalkers. The switch is at the far end of this room. Once you've pressed the switch, you have to work your way back out of the maze to the teleporter you passed at the start. This will take you back to the start of the map.
The Planet Gem
You've pressed all three switches. Turn around from the start to see it sitting on a small pedestal in the middle of a pool of slime, that the three switches raised.
Simply pick it up and you've got the map's gem. Return to Hub 1: Blight (map).