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Skyrim Skills and Perks Guide: Sneak
http://www.rarityguide.com/articles/articles/1073/1/Skyrim-Skills-and-Perks-Guide-Sneak/Page1.html
By chronodev (Ron)
Published on 11/27/2011
 
A guide to the Sneak Skill Tree and Sneak Perks on Elder Scrolls V Skyrim

Sneak is the art of moving unseen and unheard. Highly skilled sneaks can even hide in plain sight.

Thieves, Assassin, and Ranger type characters should spend points in the Sneak skill tree. Warriors wearing heavy armor should probably not spend any points here.

Level up sneak by sneaking successfully near enemies. Just sneaking where noone is looking does not increase the skill. You can also talk to a trainer to increase Sneak

TRAINERS

Journeyman Trainer: Khayla (Khajiit Caravans)
Expert Trainer: Garvey (Markarth)
Master Trainer: Delven Mallory, (Riften)

PERKS

Stealth
(1/2/3/4/5)
You are 20/25/30/35/40% harder to detect when sneaking
Requires: Sneak 0/20/40/60/80

Note: Take this perk as soon as you can if you are a stealth character. Even if you are not a stealth character, it can be useful to spend one point in this perk as you might find yourself needing to sneak sometime

Backstab
Sneak attacks with one-handed weapons now do six times damage.
Requires: Stealth, Sneak 30

Note: Take this perk for massive damage when doing a sneak surprise attack on an enemy

Deadly Aim
Sneak attacks with bows now do three times damage
Requires: Backstab, Sneak 40

Note: Take this perk if you also use a bow.

Assassin's Blade
Sneak attacks with daggers now do a total of fifteen times total damage
Requires: Deadly Aim, Sneak 50

Note: Massive damage bonus for a sneak attack with a dagger makes this perk a good choice, although ignore this perk if you do not like to use daggers.

Muffled Movement
Noise from armor is reduced 50%
Requires: Stealth, Sneak 30

Take this perk to help you sneak more quietly. Although if you wear heavy armor, this skill will still not reduce your noise level enough to be able to sneak effectively

Light Foot
You won't trigger pressure plates
Requires: Muffled Movement, Sneak 40

Note: Can be useful if you find yourself setting many traps...

Silent Roll
Sprinting while sneaking executes a silent forward roll
Requires: Light Foot, Sneak 50

Note: Useful for quickly sneaking into cover

Silence
Walking and running does not affect detection
Requires: Silent Roll, Sneak 70

Note: Great perk to help you sneak more effectively

Shadow Warrior
Crouching stops combat for a moment and forces distant opponents to search for a target
Requires: Silence, Sneak 100

Note: Cool perk which can buy you some time in combat.