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I've been a long time forum watcher so to speak and have decided to throw a question out there, in the last week I faced my friend's Beastmen and he has all the nasty tricks, Bestigor horde with lore of beasts support, Gor horde with Beast Banner, and a whole mess of Bray Shamans level one with the Herd Stone Shard. Its messy business. Anyway, I'm wondering what combos or units you all have had luck with against the cloven ones.
Okay, so at the risk of teaching granny to suck eggs, I've got a general tactic for this - apologies if you know this, but it's worth mentioning in case you don't. The best way to beat this is to hit him in the flank with a big unit. Remember, the unit with the most ranks is steadfast, so if he's in horde he's likely to only have 4 or 5 ranks. If you can get a unit of, say 30 or 35 in a column formation (like 5 wide or something) into his flank, he should go down fairly quickly. Obviously this will take a bit of skill to do, especially as an O&G player, when you've got animosity to worry about (put a cheap black orc hero with no upgrades in the unit - works for me) and slow infantry blocks, but that's Warhammer, right?
UNDER NO CIRCUMSTANCES should you engage him to the front and expect to win - what you want to do is pull his units into a position where you want them - charge him (or let him charge) with a unit of night goblins in a narrow (5-wide) formation. This unit must be small enough that you will lose the fight and break from combat (so you're aiming to lose combat by at least 3...) but big enough so that there will still be models left. Put some fanatics in for fun if you like. The idea of this is that his Hatred will force him to pursue your fleeing unit, hopefully exposing his flank in the process. It doesn't matter whether he catches the goblins or not (this is a sacrificial unit). It's a risky tactic, but if it works it will work very well. You have to think about things like the hatred re-roll, characters with magic swords, the augments from beasts magic and stuff, but it's possible to build a sacrifical goblin block which will lose and flee, but not die (just hope you don't roll snake-eyes on the break test).
What you're aiming for is if you can get a night goblin block in the way of one of his hordes, he can either charge it and expose his flank, or stay put. If he stays put, you can block his movement by putting units close enough to stop him wheeling, or to threaten his flank if he elects to reform or turn - but you take the unit out of the game for a while. If he charges, exposes his flank, you get a big nasty block of choppy-killy-orcyness into him...
In terms of units/combos, I'd say your best bet is the savage orc big un death star - 30 or more, 2 choppas each, with lv 2 and shrunken head. A black orc warboss or your general to deal with animosity and suppress frenzy, etc. Support with a couple of units of night goblins (30 night gobs + fc is dirt cheap and good for getting in the way), chariots and trolls. Take a couple of goblin shamans with scrolls of some variety - so the dispel scroll and maybe the feedback scroll, to help deal with his magic.
One final thing to say on this: BEWARE OF THE STUBBORN CROWN! If he has this, everything I've said here won't work as well. You can still win, you just need to get him in the flank and threaten him from another angle - but the golden rule is NEVER EVER EVER charge/engage him in the front, if he is in horde formation, unless you want to give him lots and lots of combat res.
This has worked for me before, but be prepared to adapt it - he will almost certainly do something to throw a spanner in the works.
Hope that helps, and good luck!
It has yet to be proven that intelligence has any survival value. - Arthur C. Clarke (1917 - 2008)
Chariots lots and lots of chariots. Hi im a beast man i have no armor please run me over. 2 units of 3 goblin chariots should in most circumstances paste this unit down to a size that is well easy to kill.
Hatred doesn't force you to pursue (that's what Frenzy does), so that Night Goblin block tactic doesn't actually work as described, if the Beastmen make their Ld test to restrain pursuit.
As for chariots, I don't find them to be terribly effective against my army (I play Beasts) - my chaff can usually get the charge on them (my dudes march, your chariots don't), and Razorgors eat through Wolf Chariot armor just fine, whereas Gobbos and Wolves need 6's to make a dent.
Most of what Vespasian said is accurate - if you fight Beastmen head on with Orcs, you will lose. They have more M (so they'll usually get the charge), more I (so they'll hit you first), and Hatred (so they'll hit you more often). Choppas certainly helps even some of that out, but it doesn't make up for all of it. What I would do is use warmachines and spells like Foot of Gork off to whittle down the numbers to the point where you have more dudes on the table, and then give it a go with numbers on your side - as Vespasian said, M4 and Animosity make out-maneuvering them a battle you're unlikely to win.