When you send the dogs to sniff towards it they keep getting side tracked like something warding it from being discovered by any means other than by chance. You almost have to pick the dogs up and place them by it for them to even see it.
The door opens easily and you see steps going down towards the central part of the keep. It is dark you may need to light some torches to see. When placing the dogs at the steps they whine and are hesitant to head down the steps.
In Character: Zork says to Durgan, "There are more of those nasty things down there. I think you should use that fireball magic and take them out before we start stepping into a whole load of crap!"
"Well now," Durgan replies. "I wouldn't want to waste that on a target I cannot see, but how about I light the way instead?"
Durgan uses an opal to cast Light and lead the way down. Sessativa stays at the rear.
You cast light with a opal, make sure to mark it off, and start heading down into the passageway. As you get down lower you can see more and more cobwebs and movement. You can see at least three large spiders looking back at you waiting to attack. They are behind some thick webs.
With a hand on his head, Durgan says, "Okay helm, don't fail me now."
He looks back and asks, "Ready?"
He vividly imagines fire as he says "Blink!"
After the fireball goes off, he braces for their attack, in case they charge.