Hi!I am new to the game,i am building an army and have a question regarding the named ringwraiths (Khamûl The Easterling,The Betrayer,The Tainted...) I dont know which are good game wise,so please help!Which are tournament worthy and you would allways include in a list?are there any bad ones?thanks

Knight of Umbar and Undying are really overpowered
Dwimmerlaik, Dark Marshall, Khamul, Shadow Lord, the Betrayer are worth it in the right armies
finally I'm not a fan of the tainted.

KoU is great for killing big enemies (of which there are many - Transfix then rock out) and the Dwimmerlaik is truly disgusting. I'm planning on running them both in concert.
The Undying is a good option if you don't need anything specific - he renders regular Nazgul a bit moot, unless you're buying them cheap.
Dark Marshall is great for infantry-heavy armies, but I've found he tends to lose his value in higher points matches where I can afford regular banners, and where he suddenly doesn't have the Will reserves to hang around.
Shadow Lord is very powerful, but very niche. I would probably stay away from him except in cav/Fell Beast-heavy lists. The Betrayer isn't really useful except in Harad armies where his special rule actually has an effect, and the Tainted is an end-game nuke, but taking him means you're losing out on a Stand Fast of your own - make sure you can afford it.
Khamul is a bit weird; the more you spend on him the better he is; he's amazing on a Fell Beast; he's the only Nazgul that can consistently beat Elves in combat (considering he can regenerate Will), but on foot he's basically worthless.
Unless your list is calling out for a specific Nazgul (like you're Harad and you want the Betrayer for all your archers) I'd stick with the Undying, the Knight of Umbar and the Dwimmerlaik, probably in that order - assuming the Witch-King isn't an option (I'm a big fan of the Witch-King on Fell Beast),

If you're mounting a Nazgul on horse there is none better than Khamul. His regen is great. KoU is good but I prefer Khamul as he isn't dependant upon his opponent being good to be good himself.

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Thanks everyone!just one more question,i would play mordor,which are good for that army?

100% Witch King

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BLACKHAWK 2010 2013 2015 DYNASTY

Mount KoU on felllbeast and he doesn't depend on anybody. I think if you would take a horse the 40 points mire to take the fellbeast are nearly allways worth it.

Especially because you're likely paying 15 for an armored horse

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BLACKHAWK 2010 2013 2015 DYNASTY

Agreed on the FB being worth it. I actually don't own a FB model so I only take Khamul on horse lol. And you're correct that the FB takes away free KOU relying on his opponent so much, I just meant that's the One way the KOU really shines over his 8 fellows.

As to the OP's question for which to take with Mordor; I'd say generic budget Wraiths are the best choice. Most of the named are weaker at one or two spells and at their points you're typically more hesitant to allow them to die

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Considering the new profiles, I'd take the Undying over an budget wraith, who is killed by Galadriel in about three rounds! With the Undying you just have to say:"Oh getting one wound, I have 20 fate rolls so who cares?!" Then transfix and kill her.

All are good. For pure support casting, the budget wraiths (2/7-10/1 or so), are probably the best because you can fit more in the list aside from them, and can fit 2 for close to the cost of a named wraith, but they will never be used for combat.
While they are technically less "points efficient" than the named wraiths, you can choose how the points are distributed, meaning more might and wounds (if you just go for the 2/7/1), which are, in a number of cases, going to be much better than the special rules. And, with more than one of them, you can deal with more threats or force spells through when you need to.


As far as named wraiths:

For combat:
Khamul (kills warriors the most efficiently; must be on fellbeast to make the most use of his special rule),
The Knight of Umbar (Great vs heroes with high fight/attacks and monsters),
The Betrayer (great for guaranteeing kills with the re-rolls to wound; gets more benefit from the fellbeast than almost all other wraiths (khamul being the only one with a larger benefit))

For spell casting:
The Witch King (Anti-wizard, extra might, fate, and spell over other named wraiths rather than a special rule)
The Undying (hardest wraith to kill; very safe, not too much risk in committing to combat, especially paired with other spell casters)

Support:
the Dark Marshal (better combat; F6, so he is better vs armies with max F5, like Rohan and most Gondor or evil armies, and he can fight non-character elves without risking a draw),
Shadow Lord (anti-shooting),
Dwimmerlaik (anti-hero; never engage in combat; vulnerable due to lack of might),
Tainted (anti-heroics: tons of potential with movement control, and probably the best wraith against(or with) cavalry; do not take without a taskmaster to boost might and don't put in combat. Probably the hardest wraith to use effectively. Would likely pair with the shadow lord in 1k+ games, but would generally not take as his role is more specific than most of the other wraiths, unless you are taking a good number of cavalry models in your force and absolutely need to control movement.)