Erdrich nexus

By kamacausey, in CoC Rules Discussion

Can someone please explain to me why you have to use the top 2 cards of your deck when you play Erdrich nexus? Obviously the first is your resource but why do you have to use one as your domain cover?

kamacausey said:

Can someone please explain to me why you have to use the top 2 cards of your deck when you play Erdrich nexus? Obviously the first is your resource but why do you have to use one as your domain cover?

In the core rules, pg. 14:

Adding a Domain
Some effects in the game allow a player to add additional domain
cards. When a player adds a new domain, he simply draws the top
card of his deck, looks at it, and then places it facedown next
to his existing domains. That card is now considered a
domain card and loses all other identification and
game functions. Resources can be added to the
new domain during the resource phase (and
via card effects) as if it were a normal domain card.
If you're playing casually, it certainly doesn't matter, but if competitively, since it's in the rules and that card has potential game impact, that's the way it is.