Firstly I must let you know that comparing these Pokemon is rather inappropriate mainly because they all serve to exhibit different roles. However I shall do as you request
Banette
I personally think that Banette is the least useful out of the 3 mainly because of it's speed and it's abilities which don't tend to be very useful as it will most likely get KOd before even getting the chance to act for it has poor bulk.
However there are 2 things that do seem to fly in the face when looking at Banette:
Pros
- High Attack Stat
- Insomnia (Ability)
Insomnia is by far it's best ability as it enables it not to fall asleep and with this and a Focus Sash equipped it can at least set up Trick Room so that it still has a form of utility and can act as a Suicide Lead. However this is it's only effective set and can be fairly easy to counter, even in it's own tier:
Cons
- Low Defense
- Shallow Movepool
- Can be stopped by: Indirect Damage thus making it deadweight
Dusclops
I believe Dusclops is the best in terms of stalling and walling as it is a massive wall should it be equipped with the Eviolite which raises it's Defense as well as Special defense by 50%. For this reason it outclasses even it's evolved form in terms of defense
So these are most likeley it's pros:
- High Defense
- High Special Defense
- Access to status inducing moves
However unlike it's evolved form it's movepool is horrible and for this reason makes it one of the largest Pokemon who are rendered completely useless once struck by taunt. It also has no form of reliable recovery and can be worn out quite easily by a status ailment itself.
Cons
- Low HP
- Shallow Movepool
- Has no access to reliable recovery
- Taunt Bait
Dusknoir
Despite the fact that it seems to be outclassed by it's own pre-evolved form in terms of defense, Dusknoir is the best balanced between the 3 ghost type Pokemon as it not only has a beautiful movepool but packs a whole bunch of defense as well. With this it is a notable tank and I personally see it to be the most versatile amongst the other 2
Pros
- Balanced Movepool
- High Defense
- High Special Defense
- Decent Attack Stat
However like it's pre-evolution there are a few things that limit it's utility for unlike it's pre-evolution, it can't afford to be induced in status
Cons
- Low HP
- Has no access to reliable recovery
- Destined for doom when struck by a status ailment
