On invisibility

[darthauthor]

Question for clarification:

Air Elementals and Entities:

These beings are invisibile.
They have no meat body or such.
So the notion is they have no body heat.

My question is, "Can they be seen on Thermo/Infra-red or does one have to have the power/spell of See the Invisible?"

[Soldier of Od]

My initial assumption is no, but I could be persuaded by somebody with greater knowledge on how thermo-imaging works that if there is maybe a significant difference between the air temperature of the air elemental and the air around it, e.g., if the elemental had just flown in from a markedly different temperature location, such as swooping down to relatively warm ground level from the cold high altitude, before having time to acclimatise. Is thermo-imaging sensitive enough to pick up this kind of thing? But in the absence of that knowledge, I say no - keep it simple.

Note that, as air elementals are pretty big and fairly careless, they might be spotted based on visible objects around them blown about as they fly past (or through).

[ShadowLogan]

Off hand I would go with No also. In the state you are looking at IINM they are considered Energy Beings. The question then is what type of energy do they appear as? (and I don't have an answer here).

[Killer Cyborg]

I think it’s safe to assume that air elementals are air temperature.

[Nekira Sudacne]

On the other hand, air elementals should always be visible on motion sensors, even when standing completely still, because by their very nature they are a swirling vortex of air that is constantly disturbing the air around it

[Grazzik]

Air elementals are different from entities, so let's treat them differently to determine the answer.

Air Elementals

• Naturally an energy being or "life-force" (Dark Conversions pg 106) from another dimension with no density.
• Energy not defined, but is dispelled when grounded with the use of iron (Dark Con pg 109). Unclear if this is an electrical property or a magical property of iron. Without qualities defined for the energy, it is GM fiat if heat is generated... "it's life, Jim, but not as we know it".
• Presents as clouds, vapor, etc. in their physical form.
• Can turn invisible, equivalent to Invisibility - Simple.
• Cannot pass through matter, as they must use cracks or holes, so their physical form has density.
• Therefore, their physical form displaces air molecules around them as they move, even when invisible.
• Displacement of air results in minute changes in kinetic energy that is what presents as heat.
• So, even if you deem the Elemental as not having a heat signature, the air around it will still have a slightly higher heat signature showing a shadow type image on a sensitive heat imaging device.

Entities

• There are many types of entities with varying qualities, so this is a generalization.
• Naturally a supernatural energy being with no density and no physical form (except tectonic and possessing entities that both assume).
• Energy not defined, but there is no mention of being dispelled when grounded by iron that I could find. Without qualities defined, it is GM fiat if heat is generated. As a GM, I'd rule that PPE or supernatural forces are not bound by laws of physics (i.e. laws of thermodynamics).
• Naturally invisible, equivalent to Invisibility - Simple.
• Can pass through matter, so no density.
• Therefore, no displacement of air molecules around them as they move, so no change in ambient heat around them.
• So, no image on a sensitive heat imaging device.

[darthauthor]

WOW Grazzik

[Killer Cyborg]

Air elementals are different from entities, so let's treat them differently to determine the answer.

Air Elementals

• Naturally an energy being or "life-force" (Dark Conversions pg 106) from another dimension with no density.
• Energy not defined, but is dispelled when grounded with the use of iron (Dark Con pg 109). Unclear if this is an electrical property or a magical property of iron. Without qualities defined for the energy, it is GM fiat if heat is generated... "it's life, Jim, but not as we know it".
• Presents as clouds, vapor, etc. in their physical form.
• Can turn invisible, equivalent to Invisibility - Simple.
• Cannot pass through matter, as they must use cracks or holes, so their physical form has density.
• Therefore, their physical form displaces air molecules around them as they move, even when invisible.
• Displacement of air results in minute changes in kinetic energy that is what presents as heat.
• So, even if you deem the Elemental as not having a heat signature, the air around it will still have a slightly higher heat signature showing a shadow type image on a sensitive heat imaging device.

DC 106
True Elementals are an energy or life-force linked to an Alien Intelligence, but have no physical body. Do anchor themselves to this world and the physical plane of existence, they must create a physical body or possess an existing body born of this reality. Without a physical body an Elemental cannot function or influence the world around it. Furthermore, if the Elemental does not assume a physical body, it will automatically return to its own dimension in 2d6 hours.

Air Elementals can't exist long without a physical body, so I assume the overall conversation is about whether they can be detected while they're in the physical body.

Typically, the body is made from air:

DC 106
An Elemental's physical body always reflects the creature's innate nature. Consequently... the Air Elemental as a vaporous cloud.

As far as I can tell, Air Elementals don't have any physical body in energy form. I can agree that it wouldn't be entirely unreasonable for a GM to rule that this energy is detectable by various technological means, but yes, it would be a house rule.

When they DO have a physical body, it's going to be made of air/vapor as a rule, and would generate no more or less heat as it moves than any other body of air/vapor.
AFAIK, this is not enough heat to be detected by heat sensors or infrared, though I'm very far from an expert.