There is often confusion as to whether a certain type of spell can affect a target, eg. Can a magician on the astral target a physical target with a mana spell? What can be seen and heard from the astral?

Hopefully, this should clear things up.

Mana and Physical Spells 

The basic rules are that: 

• a physical entity can affect a phyical entity with type P or M
• an astral entity can affect an astral target with type Monly 

This means that a physical entity can’t affect an astral target and an astral entity can’t affect a physical target (p. 282, SR5).

On the surface of it, this seems to indicate that spirits (or astrally projecting magicians) can’t affect physical targets, which is true, provided they stay on the astral.

However, under certain circumstances, a physical entity can also become an astral entity at the same time, and likewise an astral entity can become a physical entity at the same time. This is known as being dual-natured.

The two main times when this happens are: 

• When a spirit (or projecting mage) materialise (p. 398, SR5) 
• When a physical entity astrally perceives (p. 312, SR5) 

There are also some other times when things are dual-natured, eg. An active focus is dual-natured also.

If you can grasp being dual-natured, then you can usually work out most astral problems.

So if a being is dual-natured, it counts as both physical and astral. So a manifested spirit (for example), because it is dual-natured, counts as both a physical entity and an astral entity. So it can attack targets on the physical plane and the astral.

This also means it can be targeted by those on the physical and astral as well.

Seeing from the Astral 

A purely astral form, which hasn’t manifested, can still see into the physical plane. They can also easily be spotted by anyone who is astrally perceiving, or is otherwise dual-natured in some way (eg. A hellhound guard dog).

However, they can only see the astral part of the target. Cyberware would show up simply as a blob of technology (probably black), as would a gun or computer.

Also, astral beings cannot hear in the physical plane, which means it’s not possible for them to talk to someone on the physical plane, until they manifest in some way. Mages on the physical plane use their psychic link to command spirits that they cannot see.

BTW, manifest and materialise are pretty much the same thing, in case you’re wondering!

But although the vision from the astral is limited in terms of physical perception, it can see great detail in the astral.

They can see astral signatures (p. 312, SR5) – when a magician casts a spell, it leaves a signature for hours after.

They can use Assensing, to tell someone’s health, their cyberware, even what type of magic they use.

They can even use astral tracking (p. 315, SR5), to locate someone from something with their signature, eg. Use their lodge, or a signature from a spell.

Hopefully, this rough overview should help to understand the fundamentals of how magic and the astral works.