Lock and Key was written in Glulx Inform, and is © 2002 by Adam Cadre.
This solution is by David Welbourn, and is based on version 1.11 of the game.
You begin the game empty-handed and locked in a dungeon cell. Examine yourself, door, window, guard, ceiling, torches, walls.
>X FLOOR. X GLINT. TAKE LINK. WAVE LINK.
Examine the blueprints, spellbook, mirror, and inventory. The intern will walk in after a couple turns; you can’t do much with him except give the blueprints to him when you’re done.
The first step is to add doors to the blueprints so that there is one route leading from the stairs to the cell, and another route leading from the cell to the stairs. No branching is permitted.
>S.S.S. E.E.E. N.W.W. N.E.E. N.W.W.W.
Place traps in the rooms leading out from the cell. Don’t put any traps in the rooms leading to the cell. Examine each of the traps in your inventory. The dragons are out of your price range, and some traps have restrictions on their placement.
Figuring out which trap ought to go where is guesswork at first. After you’ve seen how Boldo escapes your traps, you’ll have a better idea how to design your dungeon.
(Note: In version 1.0, you could win the game without the gladiator and dart traps in your design. That shortcut is no longer possible.)
>PUT FIRE TRAP IN C4. PUT MIST IN C3. PUT DOGS IN C2.
>PUT LION IN B2. PUT WALLS IN B3. PUT GLADIATOR IN B4.
>PUT MAZE IN A4. PUT DART IN A3.
>PUT TRAP DOOR IN A2. PUT FISH IN A2. PUT BELLS IN A2.
You should probably save the game at this point, since buying a trap commits you. You cannot move a trap once it’s been bought.
You can buy each trap individually, and really, you should at least once, since the conversations with each trap dealer are quite amusing. But after a few repetitions through the game, you’ll want to use QBUY to speed up the process.
>GIVE BLUEPRINT TO INTERN.
It doesn’t matter what you do here. To zoom through this part, just type Z. Z. Z. Z.
>X BOLDO. X THRONE. X KING. X ME.
Now you find out how good your dungeon design works. Mostly, you just watch, but timing is critical for when you use the bells. Only the experimental high-pitched bells will wake the dogs; you want to pull the lever when Boldo is in C3 and about to enter C2 (where the dogs are). Likewise, you want to ring the normal bells when Boldo attempts to charm the lion with music.
>Z.Z.Z. Z.Z.Z. Z.Z.Z.