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I was looking through the Hordes of Chaos book and on GW website and ran into something I couldn't figure out. When it comes to Flamers of Tzeentch the HoC book just says they have to start attached to a unit of Horrors and says they are played as single models. However, on the GW site if you ck up on Flamers it says that they can be fielded in units of 5-10. Is this just a little screw up on the website? Thanks.
The army list section in the back half has all the info you need.
Up to 4 flamers can be taken with each horror unit. And horror units are 10+ so I have no idea where they got the 5-10.
The 5-10 comes from the Daemonic Legion list (from the Storm of Chaos campaign book)
On their site they seem to have forgotten that the flamers, depending on what list you use, have different modi of deployment
It ain't easy bein' green... :-)
Indeed, however I would recommend using the Hordes of Chaos variant. Various tournaments do not allow Daemonic Legions, although the GT does.