I am trying to infiltrate Sundercliff Watch as a wizard. I had a plan to use as much chameleon as I could (80%) and cast frenzy on the enemies I see. The objective was to get the NPCs to kill each other and I clean up what's left. Problem is, no matter how sneaky I am, I get seen every time I cast frenzy. And isn't the point of frenzy to have the NPC attack anyone close to them? NOPE. The frenzied NPC instead attacks me right away (joined by his friends). So what's the secret to stealthy frenzy?

Forget frenzy. A 1-second Command Humanoid spell works wonders; a 1-second Drain Speed 100 spell is fun too.

Kris is right.

Drain speed x 1 sec + Command Humanoid (max magnitude) x 1 sec. Cast this while you are hidden.
(The drain speed makes your enemy 'forget' they were just hit by a spell so you remain undetected by them if you are reasonalbly well hidden.)

Or combine your command humanoid spell to include a brief invis on self. If you are still having problems, add a clannfear into this spell to get their attention while you invisibly laugh.

chameleon has to be 100% to be effective. are you wearing any armor? at higher levels, you will need 100% spell effectiveness to cast spells like frenzy.

Frenzy does work well in other places, it's just that Sundercliff Watch is different and for some reason the aggro rules are not the same. However, Drain Speed and Command spells work everywhere, and with more effectiveness than Frenzy; I have used Frenzy effectively in Lake Arrius Caverns.

but if you have commond spell for 1 sec wont they no longer be your allies basically by teh time the glow efects of the spell vanish ??

With any of the spells mentioned, you're just trying to start a fight among the enemies. Once the affected target attacks another enemy, it's self-sustaining, and the spell is no longer needed, especially if they've forgotten who started it!

but isnt 1 second less time than one can pull out a weapon and start a fight ?

Yes, completing the action takes longer than making the decision. You command them to attack, and that's equivalent to the other enemy hitting them and provoking one. They have no reason to change their target after the spell expires, so they continue. Then it feeds itself.

Best to cast the spell when no one is looking your way since spells have a momentary burst of light when cast.

You don't need 100% chameleon if you have a high enough sneak. Although the 100% spell effectiveness i believe would be required