Everyone knows the big bad Belakor and his mastery of the fearsome invisibility, but what of his other power, Shrouding? Cover is one of the most abusable parts of warhammer 40,000, and Chaos has a character that can get it 100% of the time each game that can jink himself. Sounds like a no-brainer to me.
While many discard this power since Belakor himself has the Shrouded special rule, this power actually gives a charging chaos army quite a bit of staying power as there are many units that have the jink special rule.
If you wrap your units around Belakor within a 6" bubble, you can give them between a 2+ or a 3+ cover save. Keep the rest of your army in reserve and charge up the board.
As you can see, the bubble is actually quite large (6" goes to the END of each die from Belakor)
I recommend taking Daemonkin as your main force or as an ally for some tough Bloodthirsters. Just have them jink with their baby toe in the bubble and you'll have a 2+ thirster. Fly for further invulnerability.
In the front of this picture you can put a number of things. I recommend taking a gorepack and doing the following
2 units of 3 bikers with meltaguns in the front (again you just need your baby toe in the bubble and declare a jink for the sweet 2+) They provide intervening model cover for your non-jinking units
2 units of 2 spawn. More wounds just in case.
Toss in your lord and dogs in there too. This is a formation with deathstar-ish survival, but has the flexibility to split apart and take out units that each piece of the formation was designed to kill.
(Please forgive the unpainted spawn, the forgefiend maulerfiend proxy, and lack of bikes in the front)
Even the Heldrake has his base in the bubble, and can jink for a 2+ if needed.
Oh, and you still have invisibility. Toss that where ever you need it. With this, your army should weather a TON of firepower and absolutely destroy in the assault phase. You could also take a
CSM tank with dirge casters to seal the deal.
Try this tactic and let me know how it goes or what you think. Also, if you have any cool tactics of your own, make your own guide too! Death to the false emperor!!!