Radiation

Radiation is a damage type specific to this setting and becoming Irradiated is a status effect caused by sustained exposure this damage.

The world is currently blanketed by radiation in varying degrees of thickness. Most living creatures do their best to stay away from places with high radiation readings; however, it's not always possible. One of the most common medical emergencies in the wastes is radiation sickness. Areas of Wild Magic found around the rifts are all smothered with heavy radiation, with the added threat of triggering the volatile magical energy via casting a spell or using an item or ability that utilizes magic in some form.

Radiation Damage

Whenever a creature takes radiation damage, their maximum HP is decreases by that amount.

This subtraction can be prevented by effects and abilities that mitigate damage, but once it is applied, it lasts until the appropriate medicine or spell is administered and cannot be removed by resting. Magic such as Lesser and Greater Restoration can remove all radiation, as can Rad-Away.

If a creature's Maximum HP is reduced to 0 by any means, they fall unconscious and make death saving throws, but can only be stabilized and can't recover HP until the source of their reduction is removed. Any further reduction to its Maximum HP that would make it lower than 0 result in the creature dying.

Becoming Irradiated

When a creature's Hit Points become reduced by half of their maximum amount by Radiation, they become Irradiated.

When a creature becomes Irradiated, they take a level of Exhaustion. Each time they finish a Long Rest while they are still Irradiated, they gain a level of Exhaustion instead of removing a level. If an Irradiated creature goes 24 hours without a Long Rest, they automatically take 2 levels of Exhaustion, instead of normal process of rolling a Constitution Save to see if they only take one.

You are Irradiated until you remove all of your radiation based HP reductions.