On Oblivion
Sneak is the art of remaining undetected. It enables you to move around unseen, pick pockets of NPCs and do more damage if you attack someone while sneaking.
 Level Perks
- Novice - You have access a 4x damage bonus for a sneak attack with a one-handed weapon or hand to hand attacks and a 2x damage bonus for marksman attacks.
- Apprentice - You have access to a 6x damage bonus when you do a sneak attack with a one-handed weapon or hand to hand attacks and a 3x damage bonus for marksman attacks.
- Journeyman - Your chances of successful sneaking are no longer reduced when you wear heavier boots.
- Expert - Your movement speed while sneaking no longer affects your chance of being detected.
- Master - Your sneak attacks ignore the opponents armor.
You gain 0.75 exp for every second sneaking undetected while a creature is around, and 2 exp every time you pickpocket an enemy even if you don't steal anything.
- Sneak everywhere you go where there are people or monsters around, you won't gain any Athletics exp while you sneak however.
- Run against an obstacle in sneak mode next to someone that is asleep. You'll remain undetected so you'll get continuous exp.
- The fastest method by far is to exploit the dedication of the Adoring Fan towards you, after you've completed The Arena. Take him to an area away from any other people, go into sneak mode and keep pickpocketing him and then exiting his item screen(Keep on pressing A then B for Xbox 360). He doesn't care if you pickpocket him and you're sneak levels go up ridiculously fast.
- If you have not completed The Arena yet, and therefore do not have access to Adoring Fan a good way to get fast and easy Sneak exp is to go to the Imperial Prison District of the Imperial City and enter The Bastion. In there you will find the Imperial City Jailor who is sitting on a chair, simply go behind him and repeatedly sneak into the wall. If you are using the Xbox 360 or PS3 version of the game then you can put a rubber band around your analogue stick so that your character will continuously walk into the wall. If you are on PC then you can use auto-run.
 Factors affecting detection chance
There are various factors that will affect the chance of an NPC detecting you, the most common and obvious factors are:
- Your Sneak skill level - Generally speaking, the higher your Sneak level is, the less chance you have of getting detected.
- Your opponents sneak level - How skilled your opponent is in Sneak also comes into play, if their Sneak level is higher than yours then the chance of detection increases significantly.
- Where you are - If you are directly in your opponents line of site then the chance of detection is much higher than when your out of their LOS. Also, if you are standing in a light area then you also have a higher chance of being detected. The brightness of the 'eye' in the middle of the screen while sneaking represents the amount of light falling on you.
- Boot weight - Unless you are a Journeyman of Sneak or better, then heavy boots raise your chance of being detected. Binding your boots to a hot key can be a good idea because sneaking in bare feet is ideal.
- Movement- Until you become an Expert in Sneak your success is also based on whether your moving or not - and how fast. You'll often be suprised how often a Guard will walk right by you if you aren't moving, but take a single step when one is near and you're caught! The slower you move while sneaking the better; running is sure way to get caught.
To pickpocket an NPC all you need to do is enter Sneak mode and walk up to and activate your victim (Instead of starting a conversation you will pick the mark's pocket). Your success depends on the same factors that determine your chance of successful sneaking. (See above)
Note: The value and weight of them item affect the difficulty of stealing it. Trying to take something expensive and heavy is much harder than something cheap and light. Sometimes you can even get caught just by looking at your opponents inventory, regardless of whether or not you've stolen something from them.
 The Eye
When you enter Sneak mode, the cross-hair in the centre of the screen turns into an eyeball. If it becomes yellow then it means that someone is about to detect you or has already detected you.
Note: It only tells you if something can detect you, not necessarily that what you are sneaking up on can detect you. E.g. A horse could detect yoy so the eyeball turns yellow when you sneak up to it, but it can't do anything (like call the Guards), so who cares!
 On Morrowind
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