"Damage" can be loosely defined as a destructive change of form, resulting in loss of original function. It may be dealt physically (through kinetic energy with force of claws, penetration of projectiles), chemically (acid, radiation altering chemical composition), or through heat (state changes, rapid expansion of volume etc.) and or other ways.
So the big decision is either we 1) describe Psionic energies as some sort of scientific phenomenon that we understand (disclaimer: I'm not a scientist) e.g. manipulation of some sort fundamental force or field, or 2) create new rules. Which I don't know how to, I look forward to your additions!
A few distinct features of the Archon's attack:
- It has a bit of range
- It has AoE, whose strength decreases from center of target
Therefore my few hypotheses are:
1) laser beam of high energy EM waves
- A stream of ionizing radiation like gamma rays that has enough energy to instantly vaporize zerglings. But then would it would be a death laser that goes through the target as well?
2) contained beam of hot plasma, alpha particles, ions etc.
- if the Dragoon can contain antimatter with Psionic powers, the Archon could contain the plasma. Being heavier, the ultrahot matter will most likely cause an explosion at the surface upon contact.
3) localized telepathic control of kinetic energy / of atoms
- a concentrated, localized Psionic storm that goes right into the fabric of energy fields and rips molecules apart. Don't know how that would work ththough.
I'd be really interested to see what people with actual particle physics knowledge will come up with though. Maybe we can even go through all units of the game at some point!