Manchineel Trees (5e Hazard)
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Manchineel Trees (Or Hippomane Mancinella)
Manchineel are often studied by mages of the D&D version of existence for their extreme natural toxicity. After all, none have been able to find evidence of magic in their nature, but many are convinced that there must be SOMETHING magical about these spiteful plants.
Regardless, Manchineel Trees are some of the most dangerous fruit-producing trees in existence, with a sap it coats itself in that acts as a horrible toxin. Without a successful DC 20 Intelligence (Nature) check, an unsuspecting traveler would have difficulty discovering the difference between these trees and any surrounding ones. Failing the check bad enough (At the DM's discretion) may even cause the victim to mistake the tree for some sort of apple tree, due to the shape and coloration of its fruit (Though clever creatures may notice that the "apples" it makes are rather small by comparison to real apples).
Smaller water sources touching parts of a Manchineel tree (Or multiples against a larger water source within reason) can carry the toxin, and if a creature is standing under the tree when it rains, the rain carries the toxin down from the leaves and is just as dangerous. The toxin can flow down-stream.
The toxin of the tree comes from the aforementioned sap, which coats the tree, it's leaves, exposed roots (If any), and fruit. Creatures that are immune to poison AND acid damage are immune to the effects of the sap. If a creature touches this milky-white sap with its bare hands, it must make a DC 30 Constitution saving throw to avoid the effects of the toxin. On a fail, the victim begins experiencing symptoms 1+ Constitution modifier minutes afterwards (Minimum 30 seconds). The first symptom is skin irritation that quickly grows to be painful and blistering, making any attack roll or skill check that requires the part of the body that is experiencing symptoms (As is likely with hands, arms, or legs and feet) occur at disadvantage. This also causes 3D6 acid damage, occurring at 1D6 each round at the start of the victim's turn until all 3 dice have been rolled (If the creature becomes immune to acid damage during these rounds, the damaging effects end instantly and further dice are not rolled even if they lose this immunity). This damage cannot be lethal unless the victim is Exhausted.
Body parts that have made contact with the toxin can spread it by touching other body parts including other creatures. If any toxin gets into the eyes of a creature, it blinds them, regardless of if they've saved or not. Blindness wears off in 3 days after other effects of the toxin end.
Other symptoms only occur if any part of the tree (Including its fruit) have been ingested (Implying the sap has been ingested, as it is the toxin). These other symptoms include an additional 7D6 acid damage (all dice for this damage are rolled at 2D6 each round at the start of the victim's turn instead of 1D6, which is still non-lethal unless the victim is Exhausted.) and a painful swelling of any contacted flesh, which invariably leads to an inability to consume anything. However, this won't close off the ability to eat entirely, and a meal can be consumed if the victim succeeds a DC 15 Constitution saving throw. If they fail the saving throw, they take 1 nonlethal acid damage, and cannot consume anything of their own free will, because of the pain, for at least 12 hours (And cannot attempt this save again until that time has passed). The damage taken by the toxin from any symptom cannot be healed until the effects of the toxin (Excluding the Blindness it can cause) has ended, even by magical means.
The last effect of the toxin is that it prevents immune and magical response to disease. While the effects of this toxin occur internally, the victim automatically fails any Constitution save against contracting disease, and cannot be magically protected from diseases including by wondrous items (Artifacts and spells at level 7 and higher can still protect against disease in spite of this effect due to their sheer power). This also means they fail Constitution saves to fight off disease and cannot be magically cured of them either. Lycanthropy infliction saves count as saves against disease in any of their forms for the sake of this hazard, as while they are curses in D&D they spread as magical diseases.
Curing this infliction of Manchineel toxin can only come from waiting 7- Constitution modifier days (Minimum 24 hours), or a spell that cures poison that has been cast at or above 7th level.