HORROR CASTLE
Solution

(You begin on an east/west path) W, N, GET GUN, S, E, E (you're outside the castle), EXAM WELL (it has a loose brick), PULL BRICK, PUSH LEVER (the gate opens), E, E, E (lost in a forest), E (continue until you reach the key), GET KEY, N, N, W (to a wooden gate), UNLOCK GATE, OPEN GATE, N, N, W, W, GET ROPE, E, E, U, IN

In the castle:
W, PULL PEGS (you trigger a trapdoor and fall into a dungeon), LASSO ROPE, GET CROWBAR, UP, E, U, N, E, GET LAMP, W, S, D, N, W, N, GET CARD, READ CARD ("17680"), DROP CARD, S, W, S, GET KNIFE, N, W, S, LIGHT LAMP, D, S, GET BLADE, N, U, N, E, N, N, UNBOLT DOOR, OUT

Outside the castle:
W, W, W, IN (into the barn), OPEN TRAP DOOR (with the crowbar), DROP CROWBAR, D (bring the lit lamp!), D, S, GET KEY, E (don't examine the coffin!), MOVE COFFIN (you find a secret tunnel), E, SHOOT MAN, DROP GUN, GET PAPER, READ PAPER ("..om the main bedroom"), DROP PAPER, W (if the spider web has covered the exit, CUT WEB with the knife), W, DROP KNIFE, W, N, U, U, OUT, E, E, E, IN

Back in castle:
S, S, E, E, S, W, UNTANGLE ROPE, GET ROPE, E, E, EXAM TABLE (it has a drawer), OPEN DRAWER (combination lock!), UNLOCK DRAWER, 17680, OPEN DRAWER (there's a black book inside), GET BOOK, OPEN BOOK (a message from someone locked away in a secret room - it's the beginning of the message found with the mutant), DROP BOOK, W, U, N, W, HELP (the bed has lots of knobs), TURN KNOB (this opens a secret passage), U, U, E (you're outside the tower and can hear screams from above), UNLOCK DOOR (with the large key), IN (the door slams shut behind you), U (here is the princess!), GET PRINCESS, SAW BARS (using the hacksaw you remove the bars blocking the window), OUT, TIE ROPE, ASK PRINCESS (she whispers: "Find an end that is not living and say LEHGXUO" - very princess-like!), D, S, S, W, W, S, S, E, S, W, W, W, W, S (you're now at a dead end - i.e. an end that is not living), LEHGXUO (you have succeeded in your mission!)

Notes:
1. Ignore the vase and ladder.
2. If you try to SHOOT MUTANT, you will miss.
3. After you've gotten the princess, you have a tendency to stumble, knock yourself unconscious, and lose the princess. Either save the game until you reach the dead end, or return to the castle where the princess has reappeared at a random location. Once you get her again, you won't have problems any more.

Jacob Gunness - 2005

Displayed on the Classic Adventures Solution Archive: http://solutionarchive.com