[VeilEm]

I like "black swan"

[cmurf]

Black swans are very particular and mate for life. I think another metaphor is needed here.

[mc32]

Icaruses? High flying, great pedigree, abundant hubris till they go over the edge unprepared.

[dclowd9901]

Doesn't exactly roll off the tongue. My vote is for "wisps". So fragile, the slightest disturbance in its reality distortion field and it ceases to exist.

[LoSboccacc]

Icarhorses

[gaius]

That term already has a well known meaning tho'