Disclaimer: I am not some sort of gaming god. I am a guy who plays occasionally and does pretty darned well in the local scene, but I'm clinically opposed to driving more than about an hour to get a tournament in, and I for damned sure am not going to spend the night in a hotel to play.
Disclaimer the Second: You will likely disagree with parts of this. That's okay--hence why it's on a discussion forum. Feel free to disagree, even vehemently. F2C, I'm looking at you here.
Disclaimer the Third: Wall of text incoming! Not for the short of attention span!
Okay, that said, let's get on to the meat.
An Ogre horde-based army is a scary prospect for a lot of players to face. There is very, very little that can deal with a properly-supported horde, and frankly, it can be a lot of fun to play as well. However, if you're trying to build a list like this, there's some things you have to keep in mind. We'll be discussing them here.Why go Horde?
To begin with, it's fun to have a huge unit that scares your opponent to see on the table. It can go through your opponent's entire army without breaking a sweat. Additionally, you have the element of points denial on your side. An Ogre horde tends to be very, very expensive and has a lot of wounds to have to get through before it gives up any VPs.
Hordes also allow for efficiency of buffs and similar effects. Casting Trollguts on a unit of 6 Ironguts is nice. Casting it on a unit of 18 is just plain mean. Also, items like the Ironcurse Icon or Rune Maw provide a more noticeable benefit to larger units.
Background-wise, it "makes sense" for Ogres to fight in a large, unruly mob, far more than having smaller groups working in tandem. YMMV, obviously.Why not to go Horde
Here's the big one: redirectors can take most of your army out of the game. You have to be very, very careful how you deal with these things, as they become a far bigger threat when you have more models and points invested in a single all-crushing horde.
Also, you may just like the MMU playstyle more. Different things work better for different people. Nothing wrong with that.Building the Horde
You're going to need to choose between Ogres, Ironguts, or Maneaters. Each of these have their own advantages, but I'm going to go ahead and recommend Ironguts. My reasoning is thus: Ironguts use up required Core percentages and are able to deal with just about anything that comes across their way, plus they can get a magic banner.
Bulls can work, but I find that S4 just doesn't have the same punch, and you'll likely be striking last anyway. If you are in a very great weapon-heavy environment, though, they can really shine. However, they are going to need some serious buffing to do the heavy lifting in your list.
Maneaters are just too expensive for me to recommend at all. They are completely disgusting, but if you are using them properly, they'll have Scout or Vanguard and as such cannot really be supported by characters.Support
This is the most important thing with hording up, in my opinion. Your support units are the bread and butter of your army, and they have got to be able to shine.
Three Sabertusks are pretty much mandatory, as is a BSB with the Rune Maw. The ability to deny a massive amount of enemy spells is too nice to give up, and likewise 'tusks are 'tusks. Always take them.
As with all Ogre lists, unless you cannot take them, take two Ironblasters. I guess they're mandatory too. Sorry, this is sort of a rough draft. You know them, you love them. They're just plain great.
A Slaughtermaster is pretty much required in all Ogre lists. Man, I'm really adding a lot of things to the mandatory list, but there's never a reason not to take an SM. Use him to buff your troops, take on scary things, and pretty much always stick around. Outside of that, I would recommend taking an additional caster or two and I really do have to give a bit of a nod to the Firebelly. Fireball is great for dealing with redirectors and the flaming attacks can strip Regeneration off a unit before your horde tears into it. A Beasts Butcher is always a good idea for giving your unit an additional point of S and T--even nastier if you go against my suggestion and take Maneaters.Support 2: Electric Boogaloo
When looking at supporting units, though, things get interesting. You already have redirectors, artillery, and a big beefy unit. Now what you need are units to support your horde directly. These units need to be strong enough to take on opposing units directly while being resilient enough to not be easy VPs for your opponent. As such, my recommendations are as follows:
Mournfang Cavalry: Goodness, I love these things. Able to take on enemy infantry head-on (well, most infantry) and difficult to get rid of. Plus, I really love the models, and that always helps. Give them Ironfists and a Dragonhide banner and there's very little these guys are going to fear.
Maneaters: The Swiss Army Knife unit. Properly geared up, they can snipe away annoying characters and still deal with pretty much anything that comes their way. Vanguard and Stubborn makes for a somewhat interesting combination as well.
Leadbelchers: Good for clearing off redirectors, but they become easy VPs a little too often for my taste.Magic Items
With this sort of list, your magic items should be supporting your army rather than overpowering your characters. My personal recommendations would be the following:
Rune Maw: Mandatory. Uber-spells are just that scary and you need to be able to ignore them as much as possible.
Dispel Scroll: Goes without saying, really.
Hellheart: Should be pretty obvious as well.
Ironcurse Icon: Another really useful item for adding some protection to the horde and it's dirt cheap.
Standard of Discipline: Your general is likely going to be Ld 8. Making him Ld 9 is well worth 15 points.
Crown of Command: Very useful, but I'm not going to call it mandatory. Spinemarrow can duplicate the effect if you get in a bind, and you'll be taking at least one Maw caster.
Dragonhide: Again, not as much mandatory as very, very good, particularly with the afore-mentioned Mournfang Cavalry.Strategery
As mentioned before, the biggest threat to this sort of list is chaff/redirectors, so focus on them as much as possible. Cast those fireballs or Bonecrunchers or whatever as often as you can and try to get rid of as much as you can. If nothing else, an Ogre character can charge out from the horde to get a second chaff unit if positioned carefully.
Aside from that, your strategy is going to largely depend on your opponent. The big goal, of course, is to use the horde to break your opponent's backbone and then suck their sweet, sweet spinal fluid. If you're playing against a completely non-shooting army (some WoC/Beastmen, etc.), you can always hang back and let your Ironblasters do their job, then charge when your opponent has weathered a storm of cannonballs.
You will take casualties inevitably. The biggest and toughest thing you'll have to learn with this sort of list is when to reform into a mini-bus to preserve points and present three tough characters to your opponent. It takes a bit of practice, but eventually you'll get the hang of it.
So, with that said, happy crunching. If you think I missed anything, please, let me know!