IF YOU ARE MY PLAYERS DO NOT LOOK AT THIS PAGE I STG.
This is a long dungeon with little down time that your players will not be able to abandon and may result in a TPK. It is intended for players levels 8+. Raid Lairs are a step up from dungeons and include wipe / tpk mechanics.
You arrive at a small metal structure atop a hill ( or something else. it must have large amounts of ground below or you can reason that it is a portal). There are hundreds of signs and marking in every language you can imagine asking you "Do Not Enter Please". Many written with trembling hands visible from the markings.
You see a declaration posted just to the left of the door from (insert relevant character to your PCs with wealth).
"Dear Traveler, I am (Insert). If you have had the unfortunate path of coming across this sign I suggest you turn back. Many have died from entering this and none have left. There have been plenty of adventurers with senses of grandiose who have entered and failed. Do not be the same. I digress.
If you so happen to defeat the magic forces inside bring me evidence of such and this paper. Best wishes Memento Mori."
The Party is greeted by a large pit with some liquid carrying pebbles that enter down. There is also a large green lantern on a hook. There is also a small layer of glass or something similar overtop the liquid.
If they players decide to take the lantern, then the glass will move out of the way opening the liquid passage way.
Once they enter they will not be able to turn around till they complete the entire raid. Make this clear though a description similar to "As you dip your foot in the water your instinct tell you it will take you down but someone couldn't possibly swim their way back up it." On a DC 14 arcana check they discover the liquid will prevent them from using magic to escape it or the raid.
If a player enters the liquid they will be slowly carried down 600 feet. If they need to breathe they can do so normally.
They will be left in a large dark cavern and will be able to see only another green lantern 100 feet forward.
If they try to use dark vision it is to no avail and they can only see the 20 feet around the lanterns.
At this point the first lantern will begin to fade. Lanterns will fade after ~7 seconds and no longer be lit after ~13.
On an arcana check DC 12 one can identify both the lantern and darkness are magical.
Upon any further analysis, the players will notice there are large stones 20 foot in diameter them at the center of one and another centered at the lantern ahead. There are abyssal runes and the floor beneath them on these tablets that glow dim.
If a player approaches the edge of the large stones, they will hear a scream (DC 16 perception). If they stand there for 10 seconds a small creature covered in chitin will run up and try to attack them but upon getting near the rune die.
These are chitin crawlers found under the creatures of the Grandiose Journey tab. 4 of them will spawn per round as the players must make their way through difficult terrain to the next lantern.
Feel free to make as many lanterns as you wish I normally run 4.
Upon standing on the stone at the last lantern a large door begins to slide open with blades sitting at the foot of the hallway behind it.
30 chitin crawlers will spawn and try to take the players off the stone and will no longer be killed if they walk onto the stone.
If they players kill all 30 chitin crawlers and stand on the stone for 4 or more rounds of combat. They will hear a click and the door is now held open.
If they wish to claim one of the blades have them roll a 1d6 to see which they find.
Soul Edict (rolled 1-3): A sword that deals 2d6 force damage and has a plus 1 to hit. It appears to be made of chitin and some green luminescent material (does not create enough light to be used as a light source).
Blessing of the Abyss (rolled 4-6): A sword that deals 3d6 piercing damage and has advantage against natural armor.
Upon crossing through the opened door a bright light will flash and reveal a large stone platform with shallow walls surrounding it. The platform is about 400 feet across. Beyond those wall a deep pit of green energy with no bottom in sight. There are holes all over the floor and walls with a Throne across from the entrance elevated about 20 feet.
Upon it sits a large chitinous green knight with dark and glowing eyes. To his sides witches with a similar energy dyed red with what appears to be blood.
There is some type of energy field in front of them.
In front of the energy field there stands alters scattered in the room about 20 chitin crawlers and a smaller deformed chitin creature with a strange blade in its hand.
(Fourth Encounter in pull down)
In this portion 1 of 2 "Wipe Mechanics" will be introduced that will be used in higher level raids.
The chitin crawlers and deformed knight begin attacking. They in a swarm surround the party.
While this is occurring the blade of the knight will be increasing in green energy. If they take more than 6 rounds to kill the knight the blade become an insta kill sword.
(Fifth Encounter and End)
If the party takes that blade and turns toward the energy field they can use it to pierce it and dissipate the magic. Doing so will destroy the sword of the deformed knight.
Then the witches will begin to sing and the party face off against the lord, the two witches, and 15 new chitin crawlers.
If the witches sing for 6 rounds. It will kill everything but them and the lord in the room.
If they win, they will receive a ring that can reverse the flow of the liquid pool and the following loot after rolling 1d6.
(Rolls 1) The Flow Key (Wonderous Rare, Requires Attunement): While concentrating, you may change the direction of water flow of an entire source.
(Rolls 2) The Crown of Chitin (Wonderous Rare): You may choose to become hidden or allied with chitin crawlers.
(Rolls 3) Fang of Ir Yut (A legendary staff, requires attunement): This adds a global modifier to spell attacks of 1 and allows the holder to hear abyssal in a soft tone.
(Rolls 4) Coda (A legendary amulet, requires attunement): Refreshes a player or creature resource to half of its max.
(Rolls 5) Song Breaker (a rare dagger): This common appearing 1d4 piercing dagger can hold a charge. It is recharged by hearing a full song. The charge will instantly break a creatures concentration if used.
(Rolls 6) Shield Breaker (A legendary great sword, requires attunement): This great sword 15 (2d10 + 6) slashing, to hit +6, is capable of instantly breaking a shield once per day.