DeceasedCrab makes Madamluna play Shadowgate - Part 8 of 11

Well, some of this was unexpected, at least.

Head back to the banquet hall and enter the left door on the upper level. When you take the horn off the floor, a flame will erupt out of nowhere and cause a Hellhound to appear in front of you. (Amazingly, the game actually calls it a Hellhound.) DO NOT USE THE SWORD ON IT. YOU WILL DIE. Instead, Use the Water on the Hellhound. Turns out it was holy water the whole time. The Hellhound will disappear. Go ahead and Take the Horn.

The right door on the upper level of the banquet hall can be unlocked with Key 5. When you enter this room, you'll meet a Sphinx. Whatever you do, don't use anything such as the Sword or the Poker on it. You won't die, but you will be taken back to the troll bridge by the Sphinx's magic. You have to go to the right to get the Sphinx to interact with you. He'll give you one of a few riddles:

You look at me, I look back, your right hand raises, I my left.  You speak, but I in vain. Mirror

Long neck, no hands, 100 legs, cannot stand.  Born of a forest nest, Against a wall I rest. Broom

First burnt and beaten, drowned and pierced with nails, then stepped on by long-faced animals. Horsehoe

It has towns, but no houses.  Forests, but no trees.  Rivers, but no fish. Map

I've no eyes, bout once did see, thoughts had I, but now I'm white, and empty. Skull

I´m a Fire´s Friend, My Body Swells With Wind. With My Nose I Blow, How The Embers Glow. Bellows

He'll tell you to bring him the answer to his riddle so you can pass. (All the riddles as well as the item you Use on the Sphinx for each are now laid out before you, courtesy of Brian Sulpher.) Bring him the corresponding riddle, and he'll let you pass.

You will then come across an observatory. Take Scroll 5 off of the table. "Observing the stars; the throne constellation appears once every five summers. Legend says that it is a portal to another land." Take the Star off of the carving on the wall, then Open the map the Star was on. Take the Rod that is uncovered.

Go up the ladder and you'll meet a beautiful girl who's been chained up. IF YOU HIT HER, SHE TURNS INTO A WOLF AND YOU WILL DIE. THE SAME THING WILL HAPPEN IF YOU TRY TO TAKE THE BLADE THAT IS NEXT TO HER. Use the Arrow on her. It's made of silver, so it'll kill her and turn her into a dead wolf. Now you can Take the Blade.

Go back to where you fought the Hellhound and go up the ladder. There will be a wyvern here. IF YOU TAKE THE TALISMAN NOW, YOU WILL DIE. That being said, Use the Star on the wyvern to kill it. You can Take the Talisman now.