Time Flower (5e Hazard)
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A time flower is a wild, colorful flower that reeks of magical energy. Such a flower only forms on a site that is historically significant, with a major event for the kingdom, world, or universe giving it life. Such flowers never seem to bloom, but legend has it that all its waiting for is the right person. In actuality, anyone that wants to see any event in the past at the area surrounding a time flower will be granted their wish, as the flower blooms to any who seek it.
When any such person touches the time flower, the flower blooms, releasing a purple gas that quickly floods a 30 foot area before dissipating (The gas only dissipates in an open area, if concealed in a room or underground or any other enclosed space, the gas takes longer to dissipate as the DM determines). Anyone that's caught in this gas must make a DC 20 Constitution saving throw or fall unconscious and be unable to breathe for as long as the gas is still there.
While unconscious, each individual caught by the gas witnesses the event in the past that made the time flower form, unless the creature that made it bloom wanted to see a different event at any point in the past before or after that important event. All of the creatures caught by the gas share the same vision, and can see, hear, and interact with each other while in the vision. However, no creature that sees the vision can interact with or change the events of the past, as it is not actual time travel.
If the gas doesn't dissipate, no creature is aware that they are in any danger, except for what they may have felt before falling unconscious. After the events the creature who made the time flower bloom wanted to see pass, all creatures awaken and the gas vanishes instantly if it hasn't already. A creature that takes damage while in the vision from a source outside the vision awakens and is immune to the effects of the time flower's gas for 24 hours. A creature can take damage from itself or another creature while within the vision, but not from any danger in the events of the vision itself. Any such damage is psychic damage, regardless of its source, and does not cause the creature to awaken.
Any inorganic material that touches a living (A time flower dies instantly if pulled or cut from the location it grew) time flower instantly crumbles to dust, but any organic material that touches a time flower is not affected. Eating a time flower in any form (Raw, cooked, or mashed into another dish) causes Witch's Curse. Thus far, the most practical way to harvest and prepare a time flower in such a way has been with bone-based instruments, something which Hags and other evil creatures found out first. More modernized settings may have alternate methods, such as specialized wooden tools or magical living ones.
A time flower that has bloomed reverts to its unbloomed form after 7 years have passed, and cannot be used again until such time passes. Some strains of the flower may take less or more time to revert, but such time is always 7 exact of a length of time. 7 eons, 7 seconds, but never 14 seconds or eons, etc. It's thought by mages that have investigated it that the gas a time flower produces in bloom is actually related to its reproduction, and that it's quick disappearance is related to some form of interplanar travel, perhaps even time travel, but none have been able to gain any use out of it because of this very nature.