Sa'rehir, or the festival of the 5 moons, is a city-wide event that transpires every six months in the City of Chaos (aka The City of Many Names). The city, on a typical day, is a primordial sea of activity. The names of locations (including the city) and laws can and will change at any moment. The festival is the only constant.
Each moon represents one of the faces of Zeztir the god of chaos and change. Each moon is given a day to celebrate its existence. But all five days are spent partaking in the same debauchery- drinking mushroom spiked ale, wearing the guises of animals and giving in to primitive urges. Anything short of murder is allowed publicly during this period. Even then, if one wanted to murder, the effects of the spiked ale tend to subdue more violent urges, and enhance sloth and gluttony.
The animalistic guises are made out of whatever material is at hand and can range from burlap sacks to fine silks. These are distributed randomly to citizens (most costumes do not last the length of the festival). The material does not signify social standing as there is no formal caste system in the City, save the head priestess and her handmaidens. Visitors are allowed to purchase an outfit and the price varies from festival to festival. The fee is just as likely to be affected by the color of the sunset as it is the scarcity of materials.
The head priestess and her maidens lock themselves in the Piebald Palace to celebrate. The priestess indulges in a rare and esoteric substance that typically goes by the street name "Cosmic Coke". Through its ingestion she hopes to commune with Zeztir and gain the knowledge to harness the ebb and flow of chaos, to save the world from it's own demise.
Cosmic Coke is actually the crystallized form of a hyper-advanced fuel. Many centuries ago a large spacecraft crashed into the planet, and had strange impacts on the land ever since. The leaking fuselage created large creamy crystals underground. Early priests harvested these stones as holy artifacts and learned to grow their own from the shards. Realizing these stones could be grounded up they were used in religious rites mixing them with beverages, food and topical creams. This typically caused temporarily and sometimes permanent insanity.
If a player ingests any amount of this fuel (which has now been mixed with many odd and rare substances to enhance growth) they must make a saving throw. On a failure- roll on the effect table below. On a save the player is thrust in to a temporary state of euphoria and restlessness. This state usually lasts 1d4+1 hours, afterwards the player is exhausted and must rest to regain their strength.
1 - The player sees the chaotic energy that outlines existence. Whenever they close their eyes they can see the outlines of everything in front of them (including things hidden behind other objects) This is disorienting and takes times to get used to. It often causes insanity from the insomnia.
2 - The player suffers from acute paranoia and must make a save the first time they meet someone. On a failure they believe that their new associate is a spawn of chaos sent to bring their end.
3 - For 1d4 days the player gets random glimpses of the future. This can range from what they will eat the next morning to the flying moons crafts that will be common in a millennia.
4 - For 1d4 days the player bleeds a purple substance from their nose whenever they exert themselves. This substance smells sickly sweet and can be used in various potions and elixirs. Often called Brain Fuel or Thought Juice.
5 - The player enters a deep meditation that lasts 2d4 days. They cannot be woken and are in a near dead state. When they awaken their Wisdom has raised 1d3 permanently. The player will also randomly spout verses of a long lost text in Space Speak.
6 - The player passes out and sees an enormous being drifting through space towards them. This vision feels as if it lasts for years when reality it lasts 30 seconds. They now believe the end is nigh and will randomly commune with this being. The true identity of this creature is known only to the game master.
7 - Purple and green scribblings begin to rise from the players skin, creating scales. Each day the player must make a saving throw, -1 for each consecutively failed day, or more words begin to rise. On a save the mysterious texts ceases to spread but are affixed to the player's body permanently. The areas can be cut but the skin heals to reveal these words once again. These runes are from a lost language that the original "Texts of Change" were written in.
8 - The player can now translate any written text, whether they understand it or not, in to a form of long lost Deep Speech. They cannot speak the translated words, due to not having the correct vocal chords, nor do they understand what they have written.
After rolling to find the side effects for a player, that player must make another saving throw or become addicted to the substance. If a player rolls the same effect again after ingesting the fuel and roll the is same result, do not ignore the roll. Instead empower the side effects, a player may actually see chaos spawn that is trying to cause violent accidents or their Thought Juice is much more potent. This is up to the game master to decide and expand upon.
(Thank you Shane Hosea for editing and consulting)