D&Dtools1

As conjure lesser midnight construct, except as noted above and as follows.
You conjure a midnight construct instead of a lesser midnight construct.
Essentia: In addition to the options listed for conjure lesser midnight construct, you gain two new options for modifying your midnight construct by investing essentia:

• Fly Speed: Bestow a fly speed of 20 feet per point of essentia invested (40 feet for 2 points of essentia, 60 feet for 3 points, and so on).
• Deadly Aura: Bestow a damaging aura.

The aura deals 1d6 points of damage per point of essentia invested (Fort half, DC 10 + 1/2 construct's HD + essentia invested) to all creatures adjacent to the construct at the end of the construct's turn.