Quest for Glory IV: Shadows of Darkness - Walkthrough

This solution assumes you haven't taken any foreign skills - that is, none
other than those standard for the class. If you add any new skills it makes
the game less fun and challenging. Imho.
Paladins use the fighter solution. You can play one if you brought a non-
thief character in from QfG2 or 3 and did the right things. It's basically a
fighter that can sense danger (but you could also watch when the autosave is
triggered, or the music changes), fight even better yet (flame weapon and
honor shield) and heal himself (but you can buy plenty of healing potions
since you don't need money anyway). So I wouldn't bother if I were you. Oh,
if you play a Wizard and become a Paladin, you have just become a fighter
with prodrigous magic skill.

---Cave of Shadows---
All: Search the three bodies. Light the torches using the flint (or a Flame
  Dart), then take the rightmost one. Open the door.
Fighter: Take sword and shield. Cross the rope hand over hand.
Wizard: Take cloth. Near the chasm, cast Levitate. This doesn't work, so use
  the cloth for a sail, then cast Levitate again.
Thief: Walk the tightrope.
All: Leave the cavern. Katrina will greet you, then leave. You'll meet her
  again later. You should go to town now; it's six screens north, one east.

---Town---
All: The first thing you see is Erana's staff. Try and pick it up. Then, go
  and speak to everybody. Also buy everything you can buy in the shop, and
  lots and lots of rations. Ask Igor about the guildhouse, then get the key
  from the burgomeister. You can train strength and climbing in there, and of
  course write your name in the guest book. Be sure to read all books on the
  shelf.
Fighter: Smash the showcase to get the fine sword. Also get the rope.
Thief: Just get the rope, forget about the sword. Now swing the rope to the
  ceiling hook and climb it. Note the scribbling in the wood. Then look at
  the painting above the bookshelf, and under the desk. Note the combination
  of hooks. Turn the clothing hooks next to the bookshelf to open the secret
  passage, then climb into the Thief Guild.
  First thing to take is the guild card; it opens the door to the left. Read
  the books on the shelf; now you can disarm the trap on the desk. Also check
  out the wall underneath the safe, both paintings and both drain grates. Use
  the dial on the safe; now open it with the combination FILCH (doh). Use the
  lockpick on the desk and read the book, now open both safes with the thief
  kit. Finally move the barrel and use the mechanism underneath. The code is
  in the book - blue blue yellow, green green green, red green red. Talk to
  the master, er, thief. You can use the exit behind him to get out of town
  if you want, but you could also have climbed the gate. By the way climbing
  out of your inn room window scores extra points.
All: Dr. Cranium's house is a large puzzle. First is the doorbell; just
  repeat the sequence shown. Next is a sliding puzzle on the far door. Then
  open the right door. Use the TRAP and identify your animal as a baby
  antwerp. Put a sandwich as bait in the TRAP, then open the left door and
  maneuver the antwerp to the key and to the exit. Use the TRAP again and
  identify a hexapod. Now open the north door and go speak to Dr. Cranium.
  Also ask for a couple of empty flasks. You can buy healing and curing
  potions here (this is copy protected, though). You needn't actually bother
  though, as you'll find a couple of heals and you don't really need cures.
Wizard: Ask for magic and you'll be given the Glide spell.
All: Next stop is the monastery in town. You can open the door with the Dark
  One symbol.
Fighter: You can also climb into the building via the window. Climb to the
  black bird statue in between the windows. If you're really strong you
  can force the cabinet open. Feed the hexapod some garlic to calm it.
Wizard: You can also Levitate into the building, but you cannot get out
  unless you have climbing skill. Fetch the black bird statue from in between
  the windows. Destroy the hexapod by Force Bolting it several times. You
  can't open the cabinet. There's only a healing potion inside anyway.
Thief: You can also climb into the building via the window. Climb to the
  black bird statue in between the windows. Pick the lock to the cabinet for
  a healing potion. Feed the hexapod some garlic to calm it.
All: Open the secret passage by pulling the right lever near the fireplace.
  Drink from the vat down there, and take the Ritual. Open the desk (i.e.
  force it, cast Open or check for traps) and read the book. The one in the
  desk, I meant, not the necrophilicon!
Thief: There's also a statue to steal downstairs. You are not to touch it
  with your bare hands, so use the shopping bag to carry it back to the guild
  and give it to the master thief.

---Woodlands---
All: Pick some flowers, then locate the Rusalka in the lake at the southwest
  and give her the flowers. Now you can talk to her. Also speak to the
  gatekeeper at the castle gate. He and the shopkeeper in town have a lot to
  say about one another, so you can keep going in between until their dialog
  is over. Now find six wiggly bushes and touch them to reveal the Leshy.
  That name is also the answer to his first riddle. Leave and return. Return
  to the swamp and take a bone from underneath the tree, then go to the Dark
  One pillar.
Fighter/Thief: Use the rope on the bonsai bush until it's loose, then climb
  to the platform above it with the rope and fetch the bush, again, with the
  rope. You may not be able to do all this yet, as it requires good throwing,
  climbing and strength scores respectively. If it doesn't work, train in
  town then return later.
Fighter: You can climb back up to the cave by pushing the obelisk.
Wizard: Force Bolt the rocks under the bonsai bush until it's loose, then
  fetch the bush. You can climb back up by Triggering the obelisk.
Thief: You can climb back up to the cave via the center platform, then by
  jumping to the topmost one.
All: Get some goo in an empty flask. You'll need two portions, three if
  you're a wizard. Now wait until nightfall. In the swamp, use some candy on
  the ground near the will-o-wisps, then catch them in a bottle. Go to the
  Dark One pillar nearby and use the wisps on it, then use the Symbol on it
  and turn it to A-V-O-O-Z-L in that order to get a part of the Ritual.
  There's also a ghost in the forest. Talk to her and help her. Return and do
  this again a couple of times until she understands she's a ghost. Now go to
  Erana's Garden and plant the bonsai bush in the hole. By the way there's
  some gold in the left lantern.
Wizard: Fetch a fruit from the tree. It restores your mana when you eat it.
  You can get one every day. Also, south of Erana's is a fountain. If you
  drink from it, a faerie will speak to you - once...
  You can get a ritual here.
All: Sleep at Erana's often, as this reveals a dream sequence.

---Baba Yaga---
All: Return to town. Talk to the old man about his ghostly wife, and he'll
  leave. There should be a gnome in the inn, during the evening hours. Speak
  to him, then go to his room the next day and hear him out. Get some corn
  from just outside town. At night, meet the ghost (now ghosts) again twice,
  and get the male ghost's hat.
  Return to the Leshy. The answer to the next question is Rusalka. He'll tell
  you about somebody hiding behind a bush. That would be to the southeast.
  Talk to the bush to make it vanish.
Wizard: Detect reveals which bush it is, and Trigger causes it to disappear
  even before you've spoken to the Leshy.
All: This is Baba Yaga's hut. Speak to the skull a lot, and mention the
  gnome. He'll agree to let you pass if you give him the hat. Now give the
  hut some corn and enter. Baba Yaga wants you to make a pie, so go and do it
  or you'll be eaten instead. Locate the vampiric elderbury bush.
Fighter/Thief: Throw rocks at the bush until berries fall off, and take them.
Wizard: Force Bolt the bush until some berries fall off. Fetch them.
All: Return to Baba Yaga. Use the bone in the grinder, then take it out in a
  potion bottle. Put the ground bone, berries and swamp goo in the pie pan,
  then use it on a skull to fry it. Enter the hut. You can get a gift of your
  choice and are thrown out. Enter again and give Baba some goo to get the
  next gift; there's two gifts, three for a wizard.
  Return to the Leshy. The answer to the next questions are, Baba Yaga and
  Elderbury.
Fighter/Thief: The final answer is Wraith. Return here one last time, and the
  Leshy will be gone.
Wizard: The final answer is Erana's Staff. Return one last time, too.
All: Return to town and feed the gnome the Good Humor Bar. You can meet him
  one last time in the inn at night, and he'll be gone too.
Fighter/Thief: At night, you can climb into the old man's house east in town.
  Look in both sides of the closet, and the desk, for some gold and a potion.
Wizard: Same here, except you Levitate instead of climbing.
Thief: You can pick the chest to obtain a locket. Also, you can break into
  the burgomaster's house via the window. Pick the lock to his desk for some
  more gold. If you tell the master thief about your ventures he'll be real
  proud.

---Gypsies---
All: By now you may have met Katrina at the town gate at dusk. You can talk
  to her, which is fun but not that useful. After a while she agrees to meet
  you at the castle gate, and then she'll ask you for a favor. Ask for
  details. She always leaves after three questions though.
  Another thing to wait for is a gypsy. One day a gypsy will be in town,
  in the prison cell. Hear everybody out, then go to the graveyard. 
Fighter: Just lift the gravestone.
Wizard: Cast a Fetch spell on the gravestone.
Thief: Use the rope on the tree for extra leverage to lift the stone.
All: One or two days from now you'll be allowed into the gypsy camp. You can
  speak to the fortune teller every day and get some more story background 
  and hints. Also she gives you something to protect you from an undead's
  life drain (either an amulet or the Aura spell).
  Some day you have to go out at night and defeat all five wraiths. Without
  their life drain they're not so tough. Search their vaults for a lot of
  treasure, a plate mail armor, and another Ritual (unless you're a wizard).
  The next Ritual is in the swamp tomb.
Fighter: One of the wraiths has a battle axe, which is a better weapon. Your
  strength should be high enough to enter the swamp without killing yourself.
  Walk around until you find the tomb. You need to kill two chernovy.
Wizard: Use the Glide spell to pass the swamp. Also cast Reversal as soon as
  you see the chernovy. The fight shouldn't be too hard, as long as you keep
  shooting large fireballs etc, which will absorb their small ones.
Thief: Jump from one solid spot to another to get past the swamp. There's
  only one chernovy this time.
All: Use the Dark One symbol on the crypt pillar, then solve the puzzle to
  get the Ritual. Apparently the code is 'Avoozl' again, but it doesn't do
  much - I am told you have to try it a dozen times or so. However you can
  also pass the puzzle by clicking beside it ten times.

---Castle---
All: Get Igor's crypt key. Now you can enter the crypt in the graveyard.
Wizard: Alternately, you could have cast Open on it.
All: Down in the crypt, use the crest on the floor to spell BORGOV in colors
  (blue, orange, etc.) then unlock the rightmost relief to enter the castle.
Thief: Most doors in the castle are locked, so you'll have to pick them.
All: The castle is large but doesn't have much of interest inside. There's
  a chest on the first floor, and on the ground floor. Both are trapped, and
  the second is guarded by a wraith. Neither contains much of interest. At
  night, you can overhear a conversation in the lower hall (do not forget to
  oil the door first!) and you can speak to Tanya in her bedroom. There's
  also some goons guarding the jail. The secret passages in the castle can be
  opened by 1.touching the bent rightmost candle, 2.turning the borgov crest
  above a bookshelf, and 3.spelling EXIT on the books in the library
Wizard: There's a fourth secret door that you can open by casting Open on a
  wall in the bedroom. This leads to the library (opposite of the EXIT door).
All: Go to the inn room late at night. You can do this either by sleeping for
  a couple of hours in your room, or by climbing/levitating inside when it's
  late. Speak to the domovoi. Return the next day and speak to him again.
  Now go to Dr. Cranium and buy the rehydration solution; this is also copy- 
  protected. Enter the monastery and use the solution on the local domovoi.
  Now that you're done here you can burn the monastery to the ground, by
  using the torch, tinderbox or Flame Dart spell on the carpet.
  Return to the inn and speak to that domovoi, then take the doll from the
  closet. Bring the doll to Tanya in the castle, and tell her about the
  sacrifice to be made. If you don't have this option, you have to click on
  Erana's staff and then ask the gypsy Magda about it.
Wizard: You now have the Summon Staff spell back.
All: Go speak to the gypsies again, asking about the dark one. Keep this up
  every day until you get a meaningful answer. Sleep in the inn at night,
  until you get a note from Katrina. When you do, go to the meeting place and
  you'll meet Ad Avis. No matter what you try you'll get captured and thrown
  in the dungeon.
Fighter: Break the chain open. Take the hammer and stake.
Wizard: Fetch the hammer and stake. Cast Open on the chain.
Thief: Pick the lock on the chain. Take the hammer and stake.
All: Enter the iron maiden. Open the coffin you find and speak to Katrina. Or
  whatever you do - she'll wake up anyway. You'll hear her part of the story,
  and she'll let you go when you agree to help.

---Avoozl---
All: You should already have five rituals; if not Magda the gypsy can tell
  you where to find the missing ones. She also has some more information on
  the dark one. Also, if you didn't see all of the Erana's Garden dream
  sequence yet, you can watch some more by sleeping there. When you're done
  (and it doesn't really matter if you take more than three days) enter the
  castle via the front entrance. You'll be 'ported to the Dark One cavern.
Fighter: Climb down using the grapnel; defeat the monster and take the book.
Wizard: Cast Calm on the monster, then Fetch on the book.
Thief: Sneak mode on; climb down using the grapnel, then take the book. Climb
  back up. Sneak mode off.
All: Cross the rope, then through the door, then use the rightmost door back
  to the room you started the game in. Go to the altar on the right and put
  the everburning torch and the dark one symbol on it. Read the Bone Ritual.
Fighter: Break open the cage.
Wizard: At the bone cage, cast flame dart, frostbite, flame dart, frostbite.
Thief: Jump out before the cage has fully closed.
All: Leave the room, then take the leftmost cavern. Climb up to the altar
  platform and read the Blood Ritual.
Fighter: Use the grapnel to get to the topmost platform and push the boulder
  down. Climb down again.
Wizard: Cast Frostbite on the source of the blood, then quickly walk under
  the blood shower.
Thief: Use the grapnel to get to the topmost platform, then jump up then
  left over the smaller platforms until you reach the exit.
All: Leave the room; take the second one from the left. Use the Breath Ritual
  on the altar, then blow the center, right and left horns. I mean the ones
  on the BOTTOM of the altar. Finally blow the top center one. Leave now.
Fighter: When you get caught in the breath, grab a plant.
Wizard: When you get caught inside the mouth, cast Calm then Open.
Thief: When you get caught in the breath, click the hand to your right a lot.
All: Take the final doorway.
  Move all the way to the upper right corner (via a long detour). Read the
  Sense Ritual, then leave the way you came. Go to the large altar and read
  the Heart Ritual, then climb the altar up to the Essence chamber.
  Watch the animation. Then tell the Ultimate Joke to Ad Avis.
Fighter: Use Erana's Staff. It'll transform into a spear; hit him with it.
Wizard: Simply cast Force Bolt. Then cast Summon Staff.
Thief: Use Erana's Staff. It'll transform into a stake. Jump at Ad Avis.
  Apparently you can also do this by throwing daggers at him. Deja vu?
All: Finally, use the staff on the crystal. You have won.

I missed 15 points for the Fighter (probably some monster I forgot to hack to
pieces) and 20 for the Thief (probably a break-in scene, or some loot in the
sheriff's house I missed). For some reason I got full score for the Wizard,
even if I never found the Faerie Queene or got the ritual from her (a bit of
cheating there...)

---Bugs (things to avoid doing to prevent crashes)---
All: When you enter the castle you are always told you hear an argument, even
  if you've already seen it. It is possible to free Tanya before hearing her
  mother cry in the night; if this happens you can hear the cry afterwards
  which ruins your game flags. If you try to pick up anything in Tanya's room
  after she and Toby are gone, the game crashes. If you enter the dungeon
  three nights after you get the geas (as you were told), the game crashes.
  When Magda tells you about the rituals, she messes up which ones you do and
  do not have yet. You can climb into the old man's house by day but you can
  only climb out by night. If you get caught by Ad Avis's hounds of death on
  the screen you meet him in, the game hangs. After Katrina releases you, if
  you go to the town entrance you'll again get caught by Ad Avis and his
  hounds of death. When you re-enter the Dark One cavern, you can exit by
  using the exit door; Katrina will meet you like she did when you first
  started the game. It takes up to eighty seconds to restore a game, even if
  you saved the game five seconds ago! It also takes at least half a minute
  for the quit button to take effect. Occasionally the main character stops
  being animated and just slides instead of walking (you can remedy this by
  messing with your speed setting). A website I read tells me the game can
  occasionally hang when entering the guildhouse, among other things.
Wizard: If you levitate into the monastery you can't get out again unless you
  have climbing skill. I can't make the faerie queen appear. When you cast a
  wrong spell inside the lung mouth, you get stuck inside permanently. Also
  when you cast anything at Ad Avis before telling the joke, you can no
  longer cast any spells.
Thief: When you jump out of the cage in the Dark One cavern, the cursor will
  only take on the hand shape no matter what you try to do.

Walkthrough by Radiant.
http://crystalshard.net