The term Lofty Skies refers to three things. Firstly, is the insanity epidemic that struck HQ before the Mysterious Somebody's reign (referred to at the time as the Affliction), and after that the PPC's golden age after he took charge. Secondly, it is the story of the MS's rise to power, written by Huinesoron. Thirdly, it is a poem written in-universe by Nyx Nightingale (and out-of-universe by Huinesoron) at some point in 2008.
Insanity is a state of mind
We who know it won't forget
Those distant days, those calm nights
Before the storms arose.
Our dreams walked the skies above,
We stood as guardians of the worlds,
Held the fire of hope aloft;
We have watched hope's light fade,
And the worlds fall to deadly power.
We have left those lofty skies,
Weathered the storms of time, and,
By day, and night, and day again
We remember the lessons of our past.
Insanity is a place.
That place is here.