1.  The only defined characteristic of a card when its not on the battlefield or the stack is its converted mana cost, which is equal to the value of the card from A=1 up to 8=8. Starting from 9 to K, the cmc counts up from 1 again, so 9=1, 10=2 and so on. It will be a blank card with no defined card type, color or abilities/effects.

1a. When naming cards, red (hearts/diamonds) cards can only become an instant, sorcery, or enchantment card. Black cards (clubs/spades) can only become an artifact, creature, or planeswalker card. You can play an enchantment creature as bestow or normal off of a red or black card.

1b. A card on the battlefield or on the stack must be a magic card. You cannot somehow have a blank (or partially defined) permanent or spell on the stack. As part of any effect that moves a card to the stack or battlefield, you must name a card. 

2.  Once per turn, you may reveal a card from your hand, then name a magic card that has its cmc and card types (refer to rule 1), and request exactly enough mana to pay for that spell (you can get mana to pay for alternate costs such as overload or bestow, but not for additional costs such as kicker or entwine). This mana must be used to play the card you name. If you successfully cast this card, it cannot be named again for the rest of the game. 

2b. Note that this action only works with cards in your hand. You cannot attempt to flashback cards from your graveyard using this method because that is normally a zone you are not allowed to cast from. Other cards such as Daxos of Meletis may modify what cards outside of your hand you are allowed to cast.

3.  You are free to play as many spells as you would like per turn, granted that you have an alternate source of mana such as Birds of Paradise, or are allowed to cast without paying mana by some effect such as cascade. 

3a. (Not sure if this rule should exist) Mana abilities from creatures generate two mana of any color instead of what they would normally generate. Mana abilities of artifacts generate one mana of any color instead of what they would normally generate. This is to buff mana generation a bit so its somewhat usable. You have the choice between using a mana dork who will in essence let you play an additional two drop every turn but you need to untap with it, or get 1 mana right away off a mana rock.  

4.  Each game, you have 15 mana to be used on abilities, additional costs or mana payments such as mana leak. This mana may not be used to cast spells except when you are casting an X spell. You may drop as much mana as you want into X. 

4a. (Not sure if this rule should exist) Loss of life caused directly from an opponent's spell with X is capped at 5. (You can pump 15 mana into Volcanic Geyser/Exsanguinate, but it will only do 5 damage/drain 5. You can still Volcanic Geyser for 5+ at a creature though.) You are free to indirectly use X to cause more than 5 life lost, such as by giving a creature +15/+0 with a Blazing Shoal or by using Volcanic Geyser for 15 at a Stuffy Doll. 

4b. If you want to activate an ability of a card in your hand such as bloodrush or cycling, you reveal a card, then name a magic card, and spend mana from your pool of 15/pay other costs such as discarding or paying life to activate the ability. If you successfully activate the ability, the card cannot be named again for the rest of the game. 

5.  If any blank card becomes referenced (such as through Duress) or targetted (such as through Zombify) the controller of the effect must define as much of a card as necessary for the effect to function. For example, discarding a card to Blast of Genius will not require you to define anything else about the card; The cmc which is already defined is enough. It will be discarded as a blank card with its cmc and not trigger any effects such as Lazav, Dimir Mastermind that are looking for specific card types. If you duress someone, and you pick a card, you will have to define its card type in this case because that is what is necessary for it to function. If you choose a 3 of diamonds and say it is an instant, it will be discarded as a instant with cmc 3 without a defined color, name or effect. Final example, if I Zombify targetting a 6 of clubs in my graveyard, it becomes a creature card. Then, if it resolves and tries to move it to the battlefield, I must then name a creature card with cmc 6 that has not yet been named (which, following it successfully entering the battlefield, will no longer be able to be named for the rest of the game.) because any card that will exist on the battlefield must be a full-fledged magic card as per rule 1b. 

5a. If there is a partially defined card that causes something to trigger and request additional information, the controller of the effect must provide that additional information while not contradicting previously given information. For example, I control a Lazav, Dimir Mastermind and you cast a Hidden Horror. You then discard 4 of spades defining it as an artifact creature card so that your Hidden Horror lives (note that you cannot define it as an artifact creature enchantment card because such a card does not exist in magic) Lazav sees a creature card with cmc 4 hitting your graveyard and asks for the rest of it. Since I control Lazav's effect, I get to define the rest of the card. However since you already defined it as an artifact creature, I am restricted to building on top of that and naming Solemn Simulacrum or Duskworker etc.

6. If there is a