Bombur is much-maligned, and very unjustly so. While he doesn't have the same level of versatility offered by other examples, he is another perfect example of a glue hero. Unobtrusive at 8 threat, a very nicely focused statline and an ability which will just help your deck run smoother - so long as your deck is a Dwarf deck. That's where he loses out on versatility, but let's not forget that Dwarves are still one of the most powerful deck types out there, so something to make a Dwarf deck function better is not exactly to be sniffed at.
So firstly, his ability is just a fantastic design. I picked him as the best designed card for the whole 5-Dwarf thing in the Hobbit boxes and I would absolutely stand by that. Without getting into mechanics yet, it's perfect design from a theme stand-point, as the quote in the flavour text illustrates - and as I recall he's also something of a favourite of Caleb's for that reason "Because he counts as two!" But then getting into the mechanics, when you've set up the idea that Dwarves really want to get up to 5 Dwarf characters as fast as possible to activate assorted abilities, since you can only have 3 heroes, having one of them count for two is the perfect way to play into this setup and speed your early game.
So let's get into the analytical section. How much of a benefit is Bombur? Well to answer that we have to consider the other cards he supports. The three allies who depend on 5 Dwarves (Glóin, Bifur and Dwalin) are less significant, though it's worth noting that since Gloin and Bifur trigger after you play them, they count themselves, so if they're the first ally you play and Bombur is one of your 3 Dwarf heroes, then you'll still get the benefits from them.The real meat of the matter is the heroes though. While you control at least 5 Dwarves, Óin gets +1 and a icon, Thorin Oakenshield gets an extra resource every round, and Ori draws an extra card every round. Now Oin is a more niche case, Dwarves tend not to particularly struggle for , but on the other hand if you're running a deck that's somewhat dependent on having access then getting it sooner is better. Thorin and Ori though, those two are where the money's at. Quite literally in the case of Thorin, but both of them are amazing, because cards and resources are the big things you need in this game. So this indicates that getting to 5 is very worth it. Furthermore, obviously getting to 5 quickly is worth it, because extra resource generation and card draw for the rest of the game is going to help more the sooner it starts - those abilities effectively gain value for each round that they're active. The question then is how much faster will you get to 5 with Bombur than without him?
So, without Bombur, say you're running the old Dwarf powerhouse of Dain/Thorin/Ori or something similar, you need to play 2 Dwarves before you hit 5. What are the chances of you being able to do that round 1? Low, there are only so many cheap Dwarf allies. You'd have better chances if you had Bifur as well as Ori, because the cheap Dwarves are in , plus Bifur could get a resource from another player for a 2-cost and a 1-cost both in round 1. Other possibilities, well if you can play Fili round 1 then you get Kili as well and instantly hit 5, but you have to be able to afford him, which means either mono- or some means of grabbing an extra resource. The spoiled but as yet unreleased Dwarven Sellsword will help as he's a 1-cost Dwarf in , so maybe with him there'll be passable chances of hitting 5 right away, but he costs you to keep him in play, and you're still effectively depending on a two-card combo appearing in your opening hand even if there are a couple of different options for each part of the combo. Hell, there's decent enough chance you won't be able to hit 5 round 2 either. It won't be a common occurrence if you're well built for it, but it can certainly happen. Meanwhile, what if we do use Bombur? We only need 1 Dwarf ally to hit 5. Erebor Record Keeper is a 1-cost Dwarf; assuming we're going for maximum benefit from 5 Dwarves, we have Thorin/Ori/Bombur and can therefore afford the 2-cost Erebor Hammersmith or Ered Nimrais Prospector instead. The Sellsword will work here as well. Or we delve into some of those tricks the Bombur-less decks use to get additional resources to try and play 2 Dwarves, but we're using them for the easier task of playing only 1 Dwarf. At its root, the difference is like the difference between looking for a 2-card combo in your opening hand and just looking for one card in your opening hand. In reality there'll be a few different options to fill either half of the combo or the single card we're looking for, but the version which only needs 1 card instead of 2 is still always going to be much more reliable. Maybe that only averages out to about an extra 1 resource and 1 card over the course of the game, maybe more, but 1 resource and 1 card can make a big difference, and it's not really fair to judge over the course of the whole game when in fact Bombur will get you that extra card and resource at the time you need them most - the early-game.
Oh, or if you're playing Trouble in Tharbad or Nin-in-Eilph, start as the first player and Thorin and Ori will get their abilities round 1. For once, Nalir is actually good for something.
Now enough about his ability to help others work better - what does Bombur do for himself? Well, as mentioned above, he has a very nice and low threat cost, only 8, and a super-focused statline. I mean, Legolas is often talked up as a great focused statline, but he has at least 2 wasted points, possibly more depending on how you feel about hit points on characters who aren't defenders. Bombur on the other hand has only 1 wasted stat point no matter how you look at it. I can't think of a better focused statline outside of Beregond (still 1 wasted point but a better distribution). Bombur does one thing, he defends, and he's pretty good at it. Yeah, he's going to take damage, but he's in the healing sphere. He's also a natural target for A Burning Brand. And all this for 8 threat? Value right there.
I'm going to come out with a Bold but True statement here: in the early-game, Bombur can help a Dwarf deck more than Dain. Dain's ultimate power cannot be denied, he's still one of the most powerful heroes in the game, if not the most. But if Thorin and Ori come online round 2 and your deck really starts to hum, that'll give you better chances of surviving an early onslaught than a and boost which doesn't really help until you have more allies, which you can't find or afford because you're short your card draw and resource generation. Ultimate power level of Dain is higher, but Bombur gets you up faster, and as we all know, the early-game is the hardest part of most quests (best case is to have both though, such as in this fellowship: ringsdb.com)
My friends, do not allow the rampant fat jokes and opinions of those who haven't tried him to continue to obfuscate the excellent but thankless work done by this sadly under-rated Dwarf hero. Vote Bombur 2016!