It's been a while since I played through ToB, and I was just wondering when it's recommended to do Watcher's Keep? I've just killed Yaga-Shura, and I'm on my way to Abizagal. Any tips?

If you've taken out Yaga-Shura, then you should be able to do it right now. Some people even do the first level in SoA Chapter 6. I personally do it straight through just after slaying Gromnir.

I agree with Decados, do WK now. There are some great items to be found there as well as the extra exp. I think Abizagal is the toughest of the six and having extra levels will make the coming fight easier.

Abazigal is just plain easy, at least in the vanilla game :p Even Draconis is harder to beat than his old man, which I find ironic.

On topic, I do WK straight after the Saradush. Kill Gromnir, get out on fresh air, set course for WK, clean it. As easy as that :D

I guess I'll drop by WK the next thing I do then! Thanks all! :)