Hello,

On the WPN site, they published some details regarding Magic Weekend: Commander

Format: Play One of the Four Decks & Use All 3 Commanders

For Magic Weekend: Commander, we’re recommending a special Commander variant to encourage players try out the new decks. It works like this.

Any player that purchases and uses an unaltered Commander 2019 deck can begin the game with up to three legendary creatures from that deck in their Command Zone.

All three legendary creatures are treated as though they have the “Partner” ability (“Partner” allows players to have multiple commanders.) Each commander functions independently, ignoring how many times the other two commanders have been cast.

Of course, players are more than welcome to join with any Commander deck they choose—and they'll have some special objectives when they do.

So, I have been wondering about this:

Do the deckbuilding rules apply for this event if a player is using a precon?
e.g. can a player choose to have no commander and play a 100 cards deck if they are running a precon C19 deck? (since it says "Any player that purchases and uses an unaltered Commander 2019 deck can begin the game with up to three legendary creatures from that deck in their Command Zone").