Allies Rule question

[EpsilonX74]

So is there any real limitations to using Allies aside from the allied force must be able to ally and the req. of 1 HQ and 1 Troop starter can you use multiple allies and can you ally with your primary faction example main force of chaos marines hq Typhus with plague marines and plague zombies, can you then have an allied force with Kharn the Betrayer with a troop choice of khorne berserkers, then to further the example could there be a 3rd allied force on the same idea Lucius with Noise marines etc.

[GossWeapon]

You cannot ally with your own codex.  The limits are you need 1 hq, 1 troop, and they have to be (not-red square ones) on the chart.  You never get a third army, you double the current detachments when you hit 2k+ points, so your allies can have 2 hq etc...

So if you take CSM as a primary you get:

1 fortification
and can ally with one of these OTHER books (in order of happiness and from memory):
demons
guard
necrons
orks
dark eldar?

when you hit 2,000 or more points (and TO/opponent is cool with it) your charts double so it becomes:

PRIMARY:
1-4 hq (need 2 min if you want more than 6 troops)
2-12 troops (need 4 min if you want more than 2 hq)
0-6 everything else (see above)

ALLY:
1-2 hq
1-4 troop
0-2 else

0-2 FORTIFICATION