Fourteen rooms of level 2, which should have me caught up to today. This is the level associated with the Sphere of Fire, and the environmental effect is that you apply the penalties for extreme heat, as per DMG p.110. I decided to try out some symmetry with this level, but I'm not sure I like the effect.
Room I: Emephity
This room should be empty of the mephits who went to fight in room VII of level 1. There is a medium treasure here, however.
Room II: Firing Line
This room has periodic lines of fire shooting across it, north-south and east-west, through the middle of the room. If you can make a DC 15 Intelligence check you can avoid the flame. Someone who has made this check can coach another person to give them advantage on the check. If you fail the check, you must make a DC 15 Dexterity save or take 4d6 fire damage with an extra save against extreme heat, half damage and no extra save for a success. If someone wants to dodge the flames, note that they are at different levels and angles each time. It's a DC 20 acrobatics check to try and dodge, giving you advantage on the reflex save. But if you fail by 10 or more you have disadvantage on the reflex save.
Room III: Mercy
This room is a temple to Ffvvv, the god of fire (DC 10 Religion to identify it as Ffvvv's). There is a round altar near the south wall carved to look like Ffvvv's fire snake form. On the altar is a stone bowl with molten metal bubbling it it. If a character puts 25 gp worth of coins in the bowl to melt, they are relieved of one level of exhaustion due to heat. If they put any coins in they should get a hint of this effect, like a whiff of cool air.
If the altar is defiled in any way the heat in this level rises, and characters must make saves against heat every 20 minutes rather than every hour. This effect lasts until the PCs suitable atone, as determined by the DM. When cooled, the molten metal in the bowl is worth 50 gp.
Room IV: Burn Baby Burn
This room has two fire elementals. No treasure.
Room V: Heated Metal
This room contains a fire elemental myrmidon. No treasure.
Room VI: Magic Brazier
In the south wall of this room there is a fire place with a fire burning in it. Inside the fire is a heap of charred and melted weapons. None of the weapons are in useful shape, but if someone pokes through them they will find a low treasure in gems. If a weapon is held in the fire, it will continue to burn for an hour, and will do an extra 1d6 fire damage while it is burning. If put in a non-magical sheath or quiver, it will burn the sheath or quiver, and any ammunition in it. At the end of the hour, any non-magical weapon subject to this effect is melted and deals half damage.
The fireplace has a chimney. A character can take 1d6 fire damage to enter the chimney and climb up it, eventually reaching an exit to the surface.
Room VII: Smokey's Nightmare
This is an empty room. The western wall has a carving of a forest fire.
Room VIII: Snakity Snakity Snake
Each wall of this room has a three foot wide brazier with a burning flame in it. If any character goes into the center of the room or if any of the brazier's are closely examined, a fire snake crawls out of each one. When one of these fire snakes dies, another one crawls out of the brazier the dead one came from. This continues until the fires in those braziers are put out. This can be done by taking an action to turn one over. They are also AC 19, 20 hp, immunity to piercing and fire damage, vulnerability to cold damage. Allow for other ways to put out the flames, but they should require a spell slot on an action. Once put out the flames do not restart.
The brazier's themselves are a medium treasure. Each one taken out by damage other than cold damage reduces the treasure by 1/4.
Room IX: Language
Each time a character says 'fire' or 'heat' in this room, a half damage fire ball goes off, centered in the middle of the room.
Room X: Reverse Pit Maneuver
There is a large pit in the middle of this room. It has what appears to be two 5' x 10' panels made to look like the floor, but those panels are now hanging down into the pit on the east and west sides. If any character moves next to the pit and tries to look down into it, it spews fire up into the room. Everyone next to the bit must make a DC 12 reflex save or take 4d6 fire damage and make another save against extreme heat. If they make the reflex save, they only take half damage and don't have to make the second save.
The pit is 30 feet deep and has a low treasure in it. After the trap is set off it makes a low hissing sound for one minute (DC 12 Perception). While it is hissing it is recharging, and it will not go off again until it is done recharging.
Room XI: Ashes, Ashes, We All Cough Cough Cough
The floor of this room is covered with a thick coat of ashes. Anyone not moving slowly and carefully will kick up a cloud of ashes, forcing everyone within 5 feet to make a DC 12 Consitituion save. Failure means they develop a hacking cough which give disadvantage to any Stealth checks involving sound. The saving throw may be repeated every hour to end the effect.
There's a low treasure in coins under the ashes, but anyone search through the ashes will definitely have to make the save against coughing.
Room XII: Pressure Cooker
The floor, walls, and ceiling of this room have a pattern of octogonal and square tiles of different red and orange stone. The octogonal tiles are pretty obviously pressure plates (Perception DC 10). Each five feet a character moves in this room sets off one of the plates, and a square on one of the walls opens up and shoots a +5, 1d10 firebolt at them. Noting that the squares in the walls can move back is also Perception DC 10.
You can avoid setting off the pressure plate for a given 5 feet with a DC 5 Acrobatics check. (I realized after posting the rest of level one that this is the second room full of pressure plates. Whoops.)
Room XIII: Coal
This room is empty except for three barrels of coal in the north east corner.
Room XIV: Columnar
Each of these four hallways has a row of twelve columns down the middle. Each column is a depiction of one deity, with the four elemental deities and then the eight regents of the dead. The first column is a depiction of Asmodeus, which is odd. While there is no set order for the regents of the dead, Anubis is always shown first, because the souls go to him first before going to another regent. Furthermore, there are only four flames on Ffvvv's column, and they are usually associated with five flames. But there is a flame on Asmodeus's column, on the contract he is holding. If that flame is pressed, the secret door in the hallway unlocks (The secret door is Perception DC 25 to notice, but DC 20 after hearing the click of it unlocking).
