Ending, plot discussion. Warning: Spoilers

[Zacas1]

I don't see any kind of rune missing...it looks complete to me. o.o

And since the next part of the sealing almost seems to be done from Althyk's Rune perspective, I really didn't see anything missing from his part of the sealing.

Look at the orb in the center... then slightly to the left... there's a blank gap where there are triangle/arrow-like runes (Or cardinal and intermediate directions if you prefer) pointing outward from where bahamut is attempting to be contained.. the arrow-like rune would be pointing ROUGHLY towards Althyk's symbol