Board Thread:Questions and Answers/@comment-5441128-20180718231606/@comment-5441128-20180915130752

Why didn't the Atlantis Expedition make reverse effect on the City's Shielding instead of draining the energy from the ZPM they could have used the energy which was firing at them like the Prior did when the first Supergate was being made but Vala used the Cargo Ship to block one of the part which caused the Supergate to explode it was not something that even those of the Ancient used.