Unit restrictions on Militarum Tempestus?

[General Strike]

I haven't picked up the astra militarum codex yet, I'm still trying to figure out what army I want to play in 8th. I'm trying to stay away from power armor for now. I would like to bring tanks and armor along with a force of MT, am I able to bring them in the same detachment?

[Feral_80]

You can bring them in the same detachment with no penalty, but having them in separate detachments would grant you a bonus: MT units benefit from their doctrine if they are taken in their own detachment with no other <regiment> units around. The stuff that is either Auxilla or otherwise has no <regiment> also does not limit their bonus.

 

So, if you are going to field only tanks (assuming you mean Leman Russ etc.) and MT, my suggestion is to keep them separated, having e.g. all MT (and Auxilla) in one battalion or whatever, and all your heavy tanks in a spearhead or whatever (and possibly more Auxilla) with your choice of <regiment>.