I wonder why you lost, since you have 3 portals under control and giants.
Our left portal actually was under contention for some time before the end. They didn't take it much but having to keep warping back and relocking it prolly kept us away from their base a lil too much. We had giants a few minutes before them, and took a portal shortly after but basically traded a portal for theirs. That wasn't too much of an issue because killing catapults is easy, but then two of us got killed on the third relocking attempt in their base, which is prolly what cost us the game because we never really recovered.
We had 3 portals at the end because they took our portal again and managed to hold it for awhile by having all three of them stick around defending it. I was AoEing the creeps but they were still advancing, so I ran and grabbed their portal while they were all occupied in our own base, and locked it as a last-ditch attempt to turn the game around. Given more time it might've succeeded, because my allies were able to get ours back after their Regulus warped down to try to stop the lock, but they managed to carry their existing creep waves, and reinforcements from their other portal, on to finish the frontal attack. Plus they prolly had some nifty items from getting kills towards the end so they could wreck stuff on their own too.
