Air sac

[Blueeyesliz]

I have 2nd batch incubation of eggs and never before cam across a air sac on the side? Also twins in large egg where one looks deceased and the other alive another egg broke I taped it that chick still alive!
And the growth is weird the eggs dark but if not for putting two lights one top
And the other bottom I would still not see
The veins or movement yet day 12 little ones seem like jello in all eggs not really developing as I would expect yet no change what so ever in temp or humidity any idea what may be going on?

 

[FrappcinoObsession]

I have 2nd batch incubation of eggs and never before cam across a air sac on the side? Also twins in large egg where one looks deceased and the other alive another egg broke I taped it that chick still alive!
And the growth is weird the eggs dark but if not for putting two lights one top
And the other bottom I would still not see
The veins or movement yet day 12 little ones seem like jello in all eggs not really developing as I would expect yet no change what so ever in temp or humidity any idea what may be going on?

Have no IDea but that happed to some eggs but broody isabelle cukoo orpington was sitting one but when I cracked it I saw a chick inside.