There's not much to say rolling on from the last post, so I'm just going to dive straight into the last special character for the Dark Angels, after this there will be the Techmarine, the Deathwing Command Squad and the Ravenwing Command Squad, then we can finally get on to some Daemon like goodness. Azrael.
Azrael is the main special character for Dark Angels, he is to Dark Angels what Ghazghkull is to Orks, what Marneus Calgar is to Space Marines and what the Swarmlord is to Tyranids, if you get where I'm going with this, he is their leader, and so if you include him in your army he must be your Warlord.
This isn't such a bad thing in the slightest, Azrael is a force multiplier to the hilt, and as such can choose his Warlord trait, so now seems like a good chance to go through the things.
Rapid Manoeuvre makes you run and turbo-boost faster, The Hunt gives you an extra point if your Warlord or his unit slays the enemy Warlord, Courage of the Lion lets units within 12” of the Warlord roll 3D6 and pick the lowest for leadership checks, For The Lion gives the Warlord and his unit Furious Charge, Brilliant Planning lets you increase or decrease each of your reserve rolls by 1 and Hold At All Costs gives the Warlord and his unit Feel No Pain when they're within 3” of an objective. None of those traits are bad at all.
As for how Azrael safeguards the Slay the Warlord point, he's ok. He's only T4 and not eternal therefore you're going to need him to be in a squad to bounce those missile hits in case he fails his save but he does have a 2+ save and 4 wounds, he also has a 6+ feel no pain, which is better than nothing.
However, my personal favourite force multiplying effect also makes him more durable. One of his chapter relics gives him and his unit a 4++ save.
When you hear Space Wolf players talking about the Guard blob, they are often saying that it is fantastic when you can get a Rune Priest with Forewarning, giving the blob a 4++ save, the problem with this is that it is random, and so you can never guarantee you'll get the power you want. With Azrael, you can, and so you don't have to rely on a Librarian to generate it.
Finally, all Dark Angels models on the board use Azrael's leadership so long as he's still alive, additionally, he makes both Ravenwing Bikers and Deathwing Terminators troops. This is fantastic if you're thinking of doing a combination of the two, but generally I feel as though you'll struggle for points. Obviously Azrael is cheaper than the combination of Sammael and Belial, however he's still not cheap, he costs more than Eldrad.
You can obviously make a Deathwing/Ravenwing list with Azrael for about 1,500pts but that doesn't mean that it's any good, you'll have to spend points on making them work well together, then once you've done that you'll have to spend more points on making Azrael useful, as otherwise he is just a tax. Aka, Guard blob.
Rounding off Azrael before getting into the nitty gritty, let's take a look at his damage output. He has a Master-Crafted, Blind, Plasma Gun for his ranged abilities, nice, considering that he's firing that at BS5, which sums up his shooting capabilities. In close combat, he is WS6 with I5, so most of the time he's striking first and well, with 4 attacks base and dual close combat weapons. With his Chapter Relic he also strikes at S6, in addition, his weapon is Master-Crafted.
However, he does suffer from the same problem as base Belial as he only wounds at AP3, the difference being that he cannot swap out his weapons for something that is AP2. AP3 is fine normally, but really you're looking for duality. In a close combat beast you need to be able to take on anything. If you're playing against a Space Marines Terminator army, Deathwing or Paladins then Azrael isn't going to be useful to you in combat.
So in short, Azrael is a fantastic force multiplier, and he's generally ok in close combat, but the latter is not a reason to spend that many points on him. You would take him in one of two situations. Either you are running a 50 man Guard blob or you want to take a mix of Deathwing Terminators and Ravenwing Knights in your Troops choices. Otherwise, he is too many points for not enough gain, but as I say, in the right list he can be very good, which is why you need to build the list around him.