With NOVUS, the intention of the game is that it is playable straight out of the box. By the Core Play rules, a given card's rarity determines how many of that card you can have in your deck.
Common (Black) - No more than 3
Uncommon (Silver) - No more than 2
Rare (Gold) - No more than 1
Promotional / Exclusive (Red) - No more than 1
Under these rules, Unique characters, locations, and other cards are limited to one IN PLAY, and follow all other deckbuilding rules normally. These are the core gameplay rules for NOVUS and this is how the game is intended to be played and customized out of the box.
NOVUS decks are built by us to conform to these rules in the box. As we release expansions and feature packs, you may customize your deck using these rules as more products are released.
Under the new Advanced Play rules, these limitations are modified somewhat. Under these rules you may have any number of each rarity in your deck, limited to three per card. However, Unique cards under Advanced Play become the only card type limited to ONE per deck. However, we can't overstress that this is a variant of normal gameplay that is suggested only for our more advanced players who wish to have unlimited customization options and play NOVUS more as a CCG style game.
Hope that helps clear things up a bit.