I can't find anything offical stating N'Zoth is the last Old God in existence.
The titans had the power to kill them but didn't for reasons stated above and ""They do not die; they do not live. They are outside the cycle." was said by Herald Volazj who is a N'raqi or faceless one who were made from Old Gods stuff. I'm going to quote this here because I don't feel like wrighting it again:
"The Pantheon realized that the Old Gods had burrowed too deep to be excised from Azeroth without killing the nascent titan, and so they ordered their servants to instead imprison the vile gods, rather than killing them. The campaign of the titan-forged to contain the remaining three was long and brutal, but eventually they succeeded in containing the Old Ones below the surface of the world."
The only reson to go through that much effort of not destroying them is because their destruction would kill Azeroth.
Scepter of the Shifting Sands was used for what now? To unseal something, something that was locked?
I'm still confused as to why you think you need to rain on everyone's parade in here by bringing up things that will most likely have nothing to do with them, them being tamables in Siliths. I've said all that needs to be said so no need for a warning.
