Rules of Planar Anomalies and Influences (Link)
Other planes of existence have fundamental properties that are vastly different than the prime material plane. Whenever a portal to another plane is opened on the material plane or in Astral Space, a planar anomaly is formed. Anomalies can also occur when magic is drawn in from another plane (such as from a warlock’s spells). The size and strength of the anomaly depends on how the portal was created and what moved through it. Weak portals create anomalies as small as 30-feet diameter around the portal’s location, while powerful ones can create anomalies that are miles wide. When a portal is closed or destroyed, the anomaly of the portal does not immediately disappear. The anomaly lingers in the area, where it becomes weaker and smaller over time. A small portal’s influence may be gone in as little as a month, while large or massive influences can last for years, if not centuries.
In addition to a portal, some exceptional monsters that originate from another plane have auras of influence. This aura moves with the creature and influences all creatures around it. Once the creature is killed or banished, the influence emitted by the creature vanishes with it, and anyone under the effects of the influence is cured of it.
Regardless of what plane the anomaly originates from, only creatures native to the prime material plane can fall victim to its influence.
Rules of Planar Anomalies and Influences
Encountering a Planar Anomaly or Influence. When you happen across a planar anomaly or influence, you must make a Charisma saving throw against the strength of the effect. On a success, you sense the effect and can choose to not enter into it. However, you can still be forcefully moved into the effect, and likewise, the effect can still be moved to envelope you (e.g. by the influencing creature moving closer to you or the gate growing in strength).
Navigating a Planar Anomaly or Influence. When you find yourself within an anomaly or influence, you become subjected to the effects described below. You make no further saves against the planar effect, unless you have a specific feature or device that allows for such. You can attempt to orient yourself within the effect as an action. When you do so, you make a Planar Walking roll against the effects DC. On a success, the effects of the plane are suppressed until the end of your next turn.
Leaving a Planar Anomaly or Influence. When you want to get out of a planar anomaly or influence, you must attempt to leave it. This can be a difficult process and is more involved than simply navigating the planar effects (as explained above). In order to leave the area of a planar effect two things must occur. First, you must be currently suppressing the effects of the planar effects. Then you can use an action to focus your soul and find a path out. When you do so, you must make a charisma saving throw against the planar effects DC. On a success, you are able to leave the planar effects area. On a failed save, you are unable to leave the effect, and any attempts to do so have you getting lost and looping back to where you started. If you are immune to the effects of a plane (e.g. having a Seimono Yurei integrated while dealing with a totemic effect) will naturally not require any of this, and can enter and exit freely with no difficulty. Lastly, another creature who is able to drag or carry you, can forcefully pull you out of the planar effect, if they are able to escape it.
Gated Plane Effects
Aberrational anomalies and effects are ones that originated from the Far Realm, the gated plane of aberrations. When encountering aberrational effects, you start dissociating from reality and experience unexplainable phenomena. In this state, your sense of time and space are warped. You are unable to perceive the proper distances between objects or locations and objects in the environment appear to move around in a chaotic, haphazard way. In addition, the passage of time seems to occur in a non-linear or obvious fashion. For example, you may experience past events or memories that are not currently happening or you may be unable to determine the causes and effects of current events.
Remaining in an aberrational effect is incredibly dangerous. The longer you stay in the planar effect, the more your conscience is altered and you will begin to lose your memories. If you spend any substantial time in an aberrational effect, you risk falling into a maze of hallucinations, memories, and unexplainable experiences before eventually losing your entire sense of yourself.
While you are within an aberrational anomaly or influence, the following effects are applied to you:
- You can not use the Dodge or Disengage actions, and you can not benefit from cover.
- You are unable to move and all creatures and objects within the effect are within 5 feet of you at all times.
- Whenever you attempt to target a creature other than yourself (e.g. an attack roll, device or feature) you must roll a D6. On a roll of 3 or less, you instead target a random creature within the effect (including yourself), other than the target or creatures native to the far realm.
- When you attempt to communicate, roll a D6. On a roll of 3 or less, the intention, and meaning of your message becomes inverted or otherwise twisted. Other creatures under the planar effect will believe the corrupted message as the true message, even if such a message would be grossly out of character for you.
Abyssal anomalies and effects are ones that originated from the Abyss, the gated plane of demons. When encountering abyssal effects, you become overwhelmed with feelings of despair and nihilism. Depending on your personality, you may succumb to wanton rage, hopelessness, listlessness, or mindless self-indulgence as a response. These emotions will alter your perception of reality, causing you to believe the worst about yourself and your current situation. You will lose all self-confidence and motivation, believing that actions furthering your goals are pointless and any challenges you face are insurmountable. You will also conclude others should not help you and that actions to help yourself or others are futile.
If you spend an extended duration near an Abyssal effect, you will become consumed by despair and become despondent. You will experience a sense of detachment from your identity forgetting your morals, goals, desires, relationships, and history. You will believe it’s fruitless to leave the Abyssal effect and will not attempt to escape. All tasks will feel mentally exhausting and eventually, you will become unresponsive and catatonic.
While you are within an abyssal anomaly or influence, the following effects are applied to you:
- You have disadvantage on all skill rolls. This effect does not alter the planar walking skill.
- You are unable to take any Reactions.
- You are unable to communicate to others beyond stifled cries, angry yells, or hopeless remarks.
- You are unable to accept any help, aid, or other beneficial actions or effects from other creatures.
Celestial anomalies and effects are ones that originated from the Celestia, the gated plane of angels. When encountering a Celestial effect, you become filled with the emotions and thoughts of others around you. Nevertheless, you experience a sense of calm and serenity, even if you know logically you shouldn’t. Depending on your personality, you may also become obsessively virtuous, humble, selfless, and reflective. These effects will alter your sense of reality, causing you to believe all creatures are friendly and deserving of your empathy and forgiveness. You lose any attachment to possessions, even ones necessary for your survival. You also become sensitive to past actions and mistakes, judging yourself for even minor transgressions and attempting to atone for them.
If you spend an extended duration near a Celestial effect, you will develop the delusion that staying in the effect will allow you attain enlightenment and begin fearing the outside world. You will begin to discard all of your possessions and forget your prior goals. Ultimately, you will even abandon the will to live, believing that death is the only way for your atone for your misdeeds and achieve tranquility.
While you are within a celestial anomaly or influence, the following effects are applied to you:
- You have disadvantage on all saving throws, except for saving throws made when entering or exiting a planar effect.
- Your Forcefield is increased by 5, and you do not benefit from any AC provided by fibers or armors.
- You can not willingly invoke harm, pain, suffering, or perform any negative actions or effects on other creatures, even if harm is done to you first. Additionally, you cannot perform actions secretly or engage in malicious activities.
- You will willingly, and without question, forfeit any materials objects to others if asked, and will provide help or assistance if you can.
- Whenever you remember or are made aware of past actions you have done that were malicious, you must make a Wisdom saving throw against the effects DC. On a failed save, you enter into a state of regret and penance, where you can not perform any actions or speak any words for a minute.
- You and all other creatures under the same effect are able to hear each other’s thoughts, and can not silence it. Even deafened creatures or ones within magical silence will hear the thoughts.
Infernal anomalies and effects are ones that originated from Hell, the gated plane of devils. When encountering an Infernal effect, you experience delusions of grandeur and begin grossly exaggerating your own importance and survival over others. You may also become unabashedly stubborn, greedy, and prideful depending on your personality. These effects will alter your sense of reality and you will become preoccupied with an irrational sense of victimization, desiring vengeance for past misdeeds (no matter how small or trivial) and see friendly actions as perceived slights or threats.
If you spend an extended duration near an Infernal effect, you will covet the effect and the way it makes you feel. You will express ownership over the effect’s source and proclaim the effect’s location to be your new home. You become paranoid of any other creature’s presence and fear that leaving the effect will let others take the effect’s source from you. You will guard the effect’s location wholeheartedly, ignoring all physical needs and refusing to leave the area, before eventually perishing from starvation or dehydration.
While you are within an infernal anomaly or influence, the following effects are applied to you:
- All of your skill modifiers are decreased to 0 and you have advantage on all skills. This effect does not alter the planar walking skill.
- You are unable to provide any help, aid, or other beneficial actions or effects to other creatures.
- Your insight, awareness, and recall are reduced to 0. Whenever they would be used, you believe whatever would be the most hindering to your personal goals.
- Your presence is increased to 30, if it is not already higher, and can not willingly accept any charm or negotiations.
- You are unable to communicate beyond praising yourself or insulting others and you cannot give suggestions or instructions to others.
Clone Plane Effects
Dream anomalies and effects are ones that originated from the Dream Plane, the clone plane of emotions and fae. Since the dream plane is tied to emotions of living creatures, physical locations in the dream plane alter to match the lingering emotions of creatures that have spent time within it. For example, a prison cell where prisoners have historically been tortured may transform into a terrifying cave and evoke a sense of hopelessness or a city park where couples have previously proposed may transform into a meadow of flowers with a river made of elixir. These transformations are tangible and physically real to you as long as you are under the Dream plane’s effects or are a native creature to the plane. You can interact with any new objects or be harmed by any obstacles or hazards.
Upon entering a Dream anomaly or effect, your appearance may shift to match what you would imagine in a dream related to the environment’s dominant emotion. This may include changing your gender, size, hair, and eyes or giving you secondary features such as horns, scales, or tails. These changes are purely cosmetic and provide no mechanical benefits for you.
While you are within a dream anomaly or influence, the following effects are applied to you:
- You automatically fail all Wisdom and Intelligence saving throws.
- Your awareness, recall, and magic are reduced to 0.
- You gain a fly speed equal to your swim speed.
- You gain a forcefield equal to your presence (if you do not already have a stronger one).
- While you are asleep, you lose 1 presence at the start of your turn (every 6 seconds). If your presence reaches 0 in this way, you dissolve into sparkles and mist.
You gain a special bonus action: Imagine. You must use this bonus action on your turn before you take any other actions or movements. When performing this action, roll must a d10 and compare it to the list below.
- On a roll of 1, you and all your gear decrease by 1 size category, to a minimum of diminutive and your fortitude is reduced by 4 (to a minimum of 1).
- On a roll of 2, all of your speeds are halved.
- On a roll of 3, you lose hit points equal to half of your intelligence.
- On a roll of 4, you gain a -2 penalty to one random ability score.
- On a roll of 5, you and all your gear increase by 1 size category, to a maximum of gigantic and your fortitude is increased by 4.
- On a roll of 6, all of your speeds are doubled.
- On a roll of 7, you recover hit points equal to half of your charisma.
- On a roll of 8, you gain a +2 bonus to one random ability score.
- On a roll of 9, all of your skill rolls and saving throws are made with a +4 modifier.
- On a roll of 10, repeat this roll twice, ignoring any further 10’s.
Totemic anomalies and effects are ones that originated from the Totem Plane, the clone plane of ideals and eidolons. A totem effect is notable for its constant, ever-present white smoke that obscures objects and creatures, reducing your visibility, but also dampens sound, causing noises and voices to become quickly muffled. Within this smoke, the physical environment is transformed to match its perfect idealized condition based on the creatures who have inhabited it. Most buildings will look to be in pristine shape and appear as their designer’s intended. Additionally, objects, regardless of their age or state, will function flawlessly and look brand new.
For more important sites though, such as a recognisable building or monument, the location may be fundamentally altered to match the predominant ideals that creatures project onto it. For example, an old and damaged statue of the first king will appear regal and fully repaired, a protected park will seem ancient and bountiful with life, and a massive corporate headquarters for an immoral company will appear as a dark tower with chains and bars covering it.
When you enter a totemic anomaly or effect, your appearance, including your physical attributes and clothing will alter to match your idealized self.
While you are within a totemic anomaly or influence, the following effects are applied to you:
- You cannot take any reactions.
- You can not use the Hide action or use any covert weapons or devices.
- Your visibility is reduced to a number of feet equal to twice your Insight.
- You have advantage on skills that have a modifier of +10 or greater, and disadvantage on all other skills. (other than planar walking)
- For every hour you spend on the plane, you must make a Charisma saving throw. The DC of the saving throw is equal to the number of hours you have spent inside the plane. On a failed save, your hit points are decreased to 0. If you die due to this effect, your body becomes intangible before fading away.
You gain a special action: Ascend. When you use this action, your current and maximum hit points are increased by 4 and you receive a -3 penalty to planar walking. In addition, the following effects occur until the start of your next turn:
- You gain a forcefield of 30
- You gain advantage on all saving throws other than charisma
- You can not be grappled, shoved, restrained, or forcefully moved
Shadow anomalies and effects are ones that originated from the Shadow Plane, the clone plane of desires and undead. Inside a shadow effect, sources of light provide no benefit, including any sunlight or technical devices. Color is darkened and heavily desaturated with environments possessing only a single saturated color accent based on the desires of creatures that have spent time within it. For example, a bank may have yellows saturated due to the desire for wealth usually seen within, whereas a Lord’s manor may have the purples highlighted due to the desire for status.
However, it is more than just light and color that is altered. The entire environment transforms to become more oppressive and challenge you. The physical landscape transforms to become one that resembles the normal world but in a state of severe disrepair. Buildings are damaged with holes in their walls and shattered windows, trees and plant life are dead, and rivers and lakes are dried up. Weather is also amplified to become harsher and more intense with a sunny day becoming a heat wave or a rainstorm changing into a monsoon.
Once you enter a shadow anomaly or effect, your appearance will alter to reflect what it would look like if you entirely lacked what you currently desire. For instance, you will appear starving if you are hungry, your skin may rot if you desire confidence or beauty, and your clothes may transform into rags if you desire wealth.
While you are within a shadow anomaly or influence, the following effects are applied to you:
- You automatically fail any saving throws to avoid being Grappled, Disarmed, or Shoved by other creatures.
- Whenever you fail a skill roll or saving throw, you gain 1 level of exhaustion.
- Whenever you succeed a skill roll or saving throw, you lose 1 level of exhaustion.
- If you remain still for more than 1 minute, you must make a Charisma saving throw against the planar effect’s DC or become restrained by the planar effect and begin suffocating.
You gain a special reaction: Overshadow. If a creature affected by the planar effect fails a skill roll, you can use a reaction to perform the same action (if able). You can choose a different target, if you so choose. On a success, you gain advantage on your next turn, and the overshadowed creature gains disadvantage on it’s next turn. On a failure, the inverse happens.