Light cave is an Egyptian Swan hatch by DToccs

I know MIB was just taunting Jack when he brought up the Swan and the button, but I think it is some interesting food for thought.

The pool with the plug is obviously man made. The screencaps of Jack standing in it show that it is made of paved bricks.
What if The ancient Egyptians who built the Temple and statue and other ruins all over the island are responsible. Maybe some Egyptian Radzincksy (who we can call Egypzcki) dug too deep in this particular spot and unleashed the engeries underneath. Now they obivously didn't have concrete and computers to cork in it like DHARMA so instead the filled it with bricks and water to hold it at bay. They placed the plug in the centre which is equivalent to the failsafe key of the Swan.

Other evidence, when Desmond pulled the plug, the energy released sound exactly like the Swan discharge from the failsafe.
What happened to Jack after turning it back on is identical to what happened to Locke and Eko after the hatch implosion, they woke up in the jungle not far from the energy source.

If the energy pocket under the Swan was 50,000 times bigger than the energy under the Orchid. The pocket under the light cave must be bigger again as if released it will destroy the island.