A good thief is observant. An unobservant one is a dead one; anyone who’s played the game knows that. You have to use sight and sound together to survive the game—especially on the expert difficulty level. For instance, did you know that there are paintings of a Hammer fighting one the Trickster’s minions in Lord Bafford’s castle? Paying attention to the details is one of the most important parts of Thief.
So, with that in mind, I’ll get right to the point. Following is a collection of things I’ve observed in the game. They’re sectioned off by topic, to make them easier to sort through, since there are a lot of them. Ones that can be considered cheating (I prefer to think of it as "taking advantage of the circumstances") I have under their own section.
I hope you learn some new things about the game from reading this and want to play it again if you’ve beaten it already…or want to start over, using these tactics, from the beginning. Enjoy. :-)

Keyboard setup

As a rule it’s a good idea to have all your controls near your hands so that you’re not reaching across half the world to use a potion. Here’s my setup, and it works pretty well for me. To each their own, I know, but I thought for some people, this might prove a learning experience. : )

W - run forward	S - backward	A - Strafe left	D - Strafe right	Q - Lean Left
E - Lean Right	R - Lean forward	~ - Sheathe Weapon	1 - Blackjack	2 - Sword
3 - Broadhead	4 - Fire Arrow	5- Gas Arrow	F1 - Water Arrow	F2 - Moss Arrow
F3 - Noisemaker Arrow	F4 - Rope Arrow	6 - Healing potion	7 - Holy Water	8 - Breathing potion
Tab - center view	z - inventory left	x - inventory right	c - use inventory	v - drop inventory
b - put away inventory	ctrl - duck	space - jump	Mouse1 - attack	mouse2 - use
mouse3 - Block	alt - speed toggle	f - gamma up	g - gamma down	t - Healing potion

I’m sure a lot of you are saying now why in the HELL are his controls set up like that? Here, I’ll explain.

W,A,S,D:	I’m so used to Quake II and other FPS that I couldn’t change my movement controls. Q2 warped my mind. : )
Q, E:	I have the lean keys right by move forward. Since I use my left middle finger to move forward, I can use my ring finger and index finger to lean.
R:	I don’t trust the "alt+shift+w" lean style, so I just made R my official lean forward key.
~:	This is the default sheathe weapon key in Thief, and I haven’t changed it.
1-5:	These are all my offensive weapons. 1 and 2 are my close range, and 3, 4, and 5 are my arrows. Works out well.
F1-F4:	These are my "passive" arrows. They’re right above my regular ones, laid out by order of usefulness. Obviously, the water arrow is going to be F1.
6-8:	These are my potions, again ranked in order of usefulness. Normally I can just go through my inventory, but if I don’t have the time, it’s nice to have a hotkey.
Tab:	When I’m fighting, I often find myself (being the freakish inverted mouse-user that I am) having a duel with my opponent’s feet. I got tired of that, so I wanted a center view key. Tab works as good as any (besides, it’s right by my ring finger.)
Z, X, C, V, B:	These are my inventory keys. I normally use my thumb or index finger to cycle through them.
Ctrl:	This is my duck key. It used to be shift, but my pinkie kept cramping up, so I put it on control.
Space:	Jump. It’s right by my thumb, and I use it all the time.
Mouse 1, 2, 3:	These were left the default. I got used to them and so I felt no need to change them.
Alt:	I have W set to run forward, so when I need to walk, I hold down alt. I never jump and walk at the same time, so I don’t have to worry about pressing both alt and space bar with my thumb at one time.
F, G:	Look for these under the "taking advantage of the circumstances" section. : )
T:	This is my most used potion, so I like to have it handy. T is right next to my lean forward key.

Thieving

Sight:

• Always use the lean keys to look around blind corners. Turn while leaning to bend around the corner.
• Leaning forward is great for looking over balconies.
• Use water arrows only if there is no other option. If there’s shadow, use it. (See Fig. 1)
• When the little yellow thing in the gem at the bottom of the screen turns red, you are completely visible. That’s bad news.
• Pay attention to the details in the levels. They can help point out secret areas, and add to the flavor of the game.
• Read every book you can. They often give clues as to where things are.
• Gold bottles are worth something. Green bottles are not. (See Fig. 2)
• If you see an enemy, stay still if you’re in shadow, and watch the path he takes. If he’s on patrol, count the seconds it takes him to go from one point to another, then make your move. Being a thief requires patience.
• Crouching makes you less visible. Movement does the exact opposite.
• Look for little things. There’s a ring on a bookshelf in Bafford’s manor that’s hardly noticeable, but worth quite a bit.
• Keep your eyes attuned to movement.
• BE OBSERVANT! Notice everything! If it helps, recite it in your head, or to a song, or anything. This will save you a lot of trouble in the game (and in real life, too…especially for those of you that keep losing your keys or wallets.)
• Look at the floor to see what kind it is. Carpet or grass is best…tile and metal is worst. And boy, do they suck.

• Listen for enemies. Distance is relative to the volume of the sound.
• Use sight and sound in conjunction.
• -Listen to the sound of the floor you’re walking on: if you think it’s too loud, use a moss arrow. They work wonders.
• Make sure your speakers are separated correctly. You don’t want sound from your left coming out of your right speaker.
• Listen to the sounds enemies make, and be sure to identify them. That way you know what you have to do to deal with them.
• Eating can give you away if you’re in shadows. Try to resist the urge to eat that apple from your inventory.
• Try to catch the conversations of guards or servants. They can give good information away, and just listening to them can be funny.
• Throwing items will make sounds that distract guards.
• Oddly, the AI doesn’t react to the sound of doors opening. Keep that in mind.
• Follow at a safe distance from enemies to keep them from hearing you.
• Crouching and walking together make you put out almost no noise.
• Be aware that most things you do make noise.

• Rope arrows help you reach high places, and can also keep you out of the visibility and reach of an enemy (at least, those without ranged attacks.) (See Fig. 3)
• Moss arrows deaden sound you make by walking.
• Water arrows are the most important thing you have in your inventory, but don’t run out of them.
• Noisemakers are great distractions. Make sure it lands far away from you.
• Keep track of the turns you take in the game. Write them down if you have to. It’s very easy to get lost.
• Constantly check your map.
• Explore every part of a level. You never know what you’ll find.

Combat

The Fighting Part of Combat

• Take enemies out from a distance, if you can. It usually takes 5-10 arrows.
• Keep the arc of the arrow in mind. The farther an enemy is, the higher you have to aim the bow.
• --Line up your target with the bottom of the bow sight (that’s the usual place that an arrow is going to make contact). (See Fig 4)
• Fire and gas arrows don’t arc. Aim at the top of the sight.
• --While you’re at it, save those kinds of arrows for the difficult enemies.
• Try to hit enemies with arrows from the shadows, or from elevated positions. It’s hard for them to see you. (See Fig 5)
• Flash bombs are THE MAN! When you’re fighting a guard, bust out your blackjack, wait for him to get close to you, and drop the bomb. He’s blinded for a second, and you can clock him in his dome. (See Fig 6, 6.1)
• When fighting with your sword, always keep block on. Jump in to attack, then jump back. Try to stay out of his range except when you’re attacking.
• When fighting groups of enemies, take out the ones with the ranged attacks first. Bowmen are more dangerous than swordsmen. (See Fig. 7)
• If you can’t take the bowmen out, at least try to get them to shoot their comrades. You’d be amazed how often that works. (See Fig. 7)
• You can pick up arrows that are shot at you.
• Use the lean keys to get close enough to blackjack someone.
• The blackjack still works when someone is alerted, but not very well. Use the sword.
• The less alerted an enemy is to you, the more damage you cause to them.
• Blocking with the blackjack looks ridiculous.
• Fighting zombies is pointless, unless there are a lot of them. Then bust out the holy water and watch them fly apart.
• If you see a guard on patrol, use a mine. He’ll stumble over it and that will end his patrolling days.
• If you don’t want to kill a guard, shoot him with arrows and he might just run away.

• Jumping and running is faster than just running.
• You run faster with no weapons.
• Chances are, if an enemy is looking for you, he’s going to find you. Keep your sword handy when you come to a stop.
• Hitting and running is a good combination.
• When running, try throwing something in another direction. Sometimes it will divert the enemy.

Taking Advantage of the Circumstances (Cheating)

As for F and G being the gamma keys, I admit that’s a little bit of a cheat. But when I have to see, I have to see. I prefer to think of them as "my eyes getting used to the darkness." I don’t use them all the time, but for the ridiculously dark levels, it beats turning the brightness up on the monitor.

Find water. For some reason, enemies can’t see you when you’re in water. If you jump out of the water, arm your bow, fire, then jump back in, you can hurt them and they won’t be able to see you.

Miscellaneous

In the dark.cfg file, you’ll see this line:

vismeter_zoom 110 ; zoom vis meter in
hpbar_zoom 110 ; zoom hp bar in

Change that 110 to 90. It shrinks the size of the gem and health shields and gives you more visible area on the screen. (You can’t see the health shields in the screenshots, but you can see the new visibility gem.)

To make the game run faster (if this is a problem for you), close everything in the taskbar (by hitting ctrl+alt+del) except for explorer, your mouse driver (if you have one), and rnaapp (if it’s open.)

Try to play the game at night, or in a dark room—this way you have no glare on your screen.

If you go on a killing spree, make sure your parents don’t blame this game.

There is some sweet artwork in the Thief .crf files. Use Winzip to open them.

Experiment with the game, and see what you can do.

Addendum by Brenden Tyo:

Ways to kill enemies:

• Humans- mines, fire arrows, broadhead arrows-aim for heart, top of head, center of back, and neck or slightly below w/ the hammer guards who have the high neck armor, gas arrows, flashbombs, blackjack :), sword- back stabbing is highly suggested unless you have some weird appreciation for dueling
• Hammer Haunts (skeletons in red)-back stabbing :), mines, fire arrows, flashbombs, duelling-extremely hard, holy water arrows #?, blackjack?
• Apparitions- back stabbing + 1 additional hit, 2 mines, a plethora of holy water arrows, 2-3 fire arrows, many b-head arrows, dueling- extremely hard, flashbombs
• Zombies- 2 holy water arrows, drowning, falling from high places, mines, fire arrows, flashbombs?
• Bugbeasts- back stabbing, blackjack- aim for nose, dueling-bad, very bad, gas, fire, and b-head arrows, mines
• Ratmen- back stabbing, blackjacking, b-head arrows-possible to kill with 1 of them, fire arrows, gas arrows, mines
• Spiders- b-head arrows-w/ red spiders, aim for neck area, blackjack- must be ducking, fire arrows, gas arrows, mines, sword
• Burricks- sword-dash by them, while hitting them as you pass, blackjack- lean forward, b-head arrows, fire arrows, gas arrows, mines

NOTE: All back stabbing and blackjacking must be done while the enemy is in an unalerted state. Drowning and plunging to a sorry death may also be possible with other enemies than what was noted, but I am unaware so I don't want to "mislead" (lack of a better word) any Thief fans. Also, I am aware that there are additional enemies than I recorded, but I don't know the methods of getting rid of them because: a) I have not come across them in the game yet or b) I have not read any posts or articles about this matter.