(This post is theory, though it is grounded in both observations from others, and those that have been made about primary source material.)
From others’ writings we have established that Nyarlathotep has some interesting effects on emotions, using his mental and energetic capabilities. Ny is very capable of manipulating others psychologically, and this carries over into his energetic makeup— as mentally based energy.
We can witness the emotional effects of his mental finesse in several stories, though perhaps the most notable is the poem where he is first significantly featured, which bears his name:
“He spoke much of the sciences—of electricity and psychology—and gave exhibitions of power which sent his spectators away speechless, yet which swelled his fame to exceeding magnitude. Men advised one another to see Nyarlathotep, and shuddered.”
Nyarlatohotep’s token behavior is mental manipulation, and his energy behaves in tadem. He tends to easily identify what one wants, deliver on it, and yet do so in a way which is twisted, unexpected, and unwanted. In addition, he is seen as at least somewhat abhorrent to many entities, while having a strong magnetism to him.
In more metaphysical terms, he likely identifies emotional energy streams of an entity, mentally figures out how to “solve” or exploit their emotional needs, and then projects a transmuted version of this back to the entity.
A simplification of this is an identification -> transmutation -> projection of energy. The energetic projection seems to the effected to originate from outside of themselves.
In more psychological terms, he pinpoints others’ emotional needs and wants, and then exploits their senses of envy and wonder in an unsavory manner.
While the above analysis sheds some light on Nyarlathotep’s energetic makeup and persona, we have not yet covered the possible energetic expression of The Shining Trapezohedron (”TST”), who is energetically associated with him somehow, and therefore is paramount to categorize.
Going through the previous analysis pattern allows the establishment of a potential pattern of energetic activity for TST as well.
In below primary source material (The Haunter of the Dark), TST is essentially an object or construct— which are not sentient. Even using this interpretation can still yield a surprising amount of insight about TST.
This passage offers some illumination about TST’s emotional effects:
“This stone, once exposed, exerted upon Blake an almost alarming fascination. He could scarcely tear his eyes from it… Into his mind floated pictures of alien orbs with great stone towers, and other orbs with titan mountains and no mark of life…”
In the above passage, TST clearly exerts some kind of emotional and mental effect on a chosen entity (whoever or whatever opens the box it is in), proceeding to project thoughts of otherworldly places into their brains, later turning to emotional horror to make them close the box (which is needed to make TST function and release the Haunter).
Lovecraftian Science cites the initial attraction to TST as being physical in origin:
“In our case this sensory method is sight… For other entities, the sensory method may be… heat or sound or even X-rays. Once this inter-dimensional connection of perception is made, complete darkness is required. Thus, it behooves the Haunter to put fear and paranoia into the receiving entity, forcing them to close the box.”
The Shining Trapezohedron (or the Haunter) notices a presence in the room, uses physical and then energetic and emotional methods to attract attention, and then uses emotional methods to compel with fear.
Energetically simplified, this is likely something like identification -> attraction -> transmutation -> projection.
Identification of an entities’ emotions leads to projecting generic attractive energy to get attention. This attention is then likely transmuted to energetically horrific energy, which then is projected back to the effected entity. This projection appears to the effected entity to originate from inside themselves, or to have an unknown origin.
Thus it is possible that TST’s energy would have the above effects on emotional energy as well, in a similar (but not totally alike) fashion to Nyarlathotep’s.
It could be argued that Nyarlathotep has these energetic effects as well, but perhaps in a different fashion when compared to TST. Therefore these effects might be more subtle in Nyarlathotep— while he is naturally charismatic, it is much more psychological at first glance, as opposed to physical.
In addition, Nyarlathotep’s energetic influence appears to victims to originate from himself, while TST’s influence appears to victims to originate from an unknown source or from inner turmoil— another key difference between the two.