How do you kill the Ceph Mastermind?

Hes the spider looking thing that throws aerial things at you. Takes place right after the gunship sequence. I've tried everything...used up all my ammo. Has to be a trick to taking him down?

Explosives. Save your bullets.

i used all the explosives. any other tactics

I hacked it, then blew it up with some explosives.

Later on I literally ran through the level running by like 4 or 5 of them. I was getting so tired of the single player campaign to be honest. The muddy, dark graphics, the horrible framerate issues (makes the game disorienting), sounds issues... It's quite sad after more than a week we haven't received a patch of any sort. :(

Yeah this campaign is a massive disappointment so far especially the audio issues too.   I realise its a short campaign but I dont even know if I am going to bother finishing it.  The 360 version has massive problems. Crysis 1 and 2 were great, this is a huge disappointment.

HOW TO BEAT CEPH MASTERMIND: when he uses his little floaty guys, hide behind a concrete wall, when they shoot, then use stealth to run around the field behind the mastermind to shoot his exposed upper back, repeat a couple times. Then when the drop pods come in, kill all of the super charged ceph with the maximum armor thing, when the mastermind starts to resurrect them again, run behind with cloak and shoot his back, repeat. The repeat the step with the floaty guys. Explosives do work best on his back but ammo works just as well...