You right to say that 100 year old half elf would look like she were in her 40s or 50s but if she were chosen she wouldn't age so I'm not giving up on that theory yet . . .

Silver fire is raw magic. All of Mystra's chosen can wield it but few others can - perhaps one or two people in a generation.


Silverfire can repair places where the weave is torn -- transforming wild magic and anti-magic zones -- and the chosen are supposed to devote some amount of time to doing this. Silverfire wielders are like the antibodies of the weave.

https://forgottenrealms.fandom.com/wiki/Silver_fire

If that is silverfire in the animation it could make for an interesting clash with Gale if he is, as I suspect, linked to the shadow weave since the clash of silverfire and shadow magic can have catastrophic effects:

https://forgottenrealms.fandom.com/wiki/Silver_fire