Play with contacts


How do I have to understand to play with Steam contacts?

I have AOE2HD plus Steam EPs. Friend has only AOE2HD. Are the new civilization by my contact installed, too, without the possibility for him to take one of them. Only the civilization of the day?
Can I still choose every civilization from my game?


Probably you both can play up to the expansion The Conquerors on-line with the same civilisations together as it’s included in all editions, but I’m not sure about this.