In modified champion deck format, can you add a third color from cards opened in packs, and do you need to run the champion+legend from the champion deck or can they be replaced/removed?

Ruling: You must keep the champion the same and stay within the original colors of the champion deck.

Nuances:

• You cannot add a third color from cards opened in packs
• The champion cannot be replaced or removed
• Full official rules were not yet available at the time of this discussion