Spearhead, and how you play it!
Basically at least, I'm not giving any detail (because I can't, I was just given a short overview)
1st: Pick your Army.
You all know the basic FoC? Can draw it while sleeping? Good. Spearhead uses the same FoC - with two major changes. The first: No minimums. You don't have to field a HQ. You don't need Core Units. The Second: There are apocalypse-datasheet-like Units. You may field as many of those as you want, though you may not duplicate any of them.
So, your army will consist of: 0 - 2 HQ, 0 - 3 Elites, 0-6 Core, 0-3 Fast attack, 0-3 Heavy support, and 0+ "Big Spearhead Units". Appearantly, if you are having a 2000 points battle, you would have to field something. Just pick your choice.
So: You don't need to field anything with a AV at all. It's just that anything with a AV will get some huge boosts.
2nd: Deployment.
Both armys are deployed at the narrow board edges. Ah, Meltaguns for infantry only work like, 12 inches? To bad. It's your fault showing up with infantry for a tank battle. Forward, for the emperor, CHARGE!! (Though, not to far forward, remember, they got meltaguns...)
3rd: Scoring units: In addition to core units, any vehicle or walker and all Spearhead-battlehosts score. Even if immobilized, stunned or shaken and/or stripped of all weapons.
And that's it. Enjoy =)