A stunlock (also called stunlocking) is the act of using multiple stuns and immobilizing effects to prevent an enemy from fighting back or escaping. As a result, a stunlock sacrifices a large amount of DPS in exchange for keeping the opponent "locked down". Although typically and most easily accomplished by a rogue, it can also be achieved to lesser degress by warriors, paladins and druids.
How to Avoid Stunlock
There are several ways to break a stunlock. The most direct method is to use a Faction Insignia (if it support breaking stuns). If an insignia is not available, there are several talents exist that increase a character's chance to resist stun effects. Finally, orcs have racial called 
[Hardiness] that gives them a 15% chance to resist stuns.
How to Perform Stunlock (Rogue)
A rogue can perform a stunlock in a variety of ways, some of which include 
[Thistle Tea] or 
[Renataki's Charm of Trickery]. A rogue's effectiveness at performing a stunlock is dependent on his or her build. For example, a full combat build or a 
[Seal Fate] build without 
[Vigor] would be least effective for stunlocking while a 
[Cold Blood] and 
[Hemorrhage] build would be most effective.
Some example stunlock strategies are:
- For a Hemorrhage build:
[Cheap Shot] -> Hemorrhage x2 -> Kidney Shot -> Hemorrhage x1 -> [Gouge].
Restealth using 
[Vanish], repeat.
- For a Hemorrhage build:
- [Cheap Shot] -> [Hemorrhage] x1 -> [Gouge] -> [Kidney Shot] .
- For a [Cold Blood]/ [Preparation]/ [Hemorrhage] build:
- [Cheap Shot] -> [Hemorrhage] -> [Gouge] -> [Kidney Shot] -> [Hemorrhage] x2 -> [Blind] -> [Slice and Dice] -> Restealth.
Once blind is about to fade:
[Cheap Shot] -> [Hemorrhage] -> 
[Gouge] -> 
[Kidney Shot] -> [Hemorrhage] x2->
[Eviscerate].
- For a [Seal Fate]/ [Vigor] build using daggers:
- [Cheap Shot] -> [Sinister Strike] -> [Gouge] -> [Kidney Shot] -> [Backstab] -> [Blind] -> Restealth.
Once blind is about to fade:
[Cheap Shot] -> 
[Backstab] -> [Kidney Shot] -> [Backstab].
(Note: If you possess 5 pieces of Nightslayer Armor you can complete the second half using [Cheap Shot] -> [Backstab] -> [Cold Blood] -> [Eviscerate])
- For a [Adrenaline Rush] build:
[Cheap Shot] -> 
[Adrenaline Rush] -> 
[Sinister Strike] -> [Gouge] -> [Kidney Shot] -> [Sinister Strike] x3 -> 
[Blind] -> Restealth.
One blind is about to fade:
[Cheap Shot] -> Wait for Energy -> [Kidney Shot] -> [Sinister Strike] x3.
It should be noted that stunlocks rarely work exactly as specified because they require a 1-on-1 situation and no extra variables like dodges or trinkets.
Applicable Mods
Stunwatch and CCwatch, both available from Curse Gaming, track the duration of your stuns allowing for better timing. Natur's EnemyCastBar (also hosted at Curse Gaming) tracks your diminishing returns, allowing the player to time the second use of his abilities in a way that does not reduce their effectiveness.