I strongly disagree with slayn's analysis because it lacks specificity. Reducing the entire spectrum of strategies to three terms significantly reduces our abillty to discuss these topics.
We need different labels for these two things, for instance:
1) Playing Ysera and having the opponent require 2 cards to remove her
2) Drawing 4 cards with sprint
Using slayn's terminology, these both represent "card advantage," but they are very different means by which to produce them and should have different labels to describe their mechanism and deck design.
Nothing? The concept needs a label, because we want to describe the concept in question. What label would you give it?
I would also say that both of those things boil down to card advantage at their core. It's all about the resources both players have at their disposal.
CA can work in "reverse", like in example 1. If Hearthstone had a card like
Mind Rot, I would argue that it's generating card advantage in the same way that your opponent spending two cards to take care of one threat is card advantage. In the case of Mind Rot, you're spending a card and not getting any cards in return, but the fact that it makes your opponent lose
two cards means you are ultimately up one card in the end. In this case and both described (Ysera, Sprint), at the end of the exchange you are up on cards/resources over your opponent which I would say constitutes card advantage.
I have no idea what kind of labels could be used to differentiate these. I suppose speaking about "value" minions as ones that are either sticky (difficult to remove and usually need multiple resources to remove) or ones that generate CA for you works decently. I think most people use the term in this way. But even then you can compare a shredder taking two cards from your opponent to remove and a Loot Horder trading with a 2 drop, but getting you a card! I would argue they're both generating CA in a similar way, even though only one actually draws you a card (that's without taking to account the fact that you need to actually spend mana on the new card or draw as opposed to the shredder's just popping right into play).
because nothing exists in a vacuum. in that case he does have minor "Card advantage", but the lost tempo vastly outweighs the advantage.
similar to how if you have tempo (major board advantage) but are at the point of top decking (horrible card advantage) the latter will greatly outweigh the former.
I think calling out 3 basic resources is fine, but you can't forsake one resource over the other one or two.
I'm not so sure about this one. Like you said, it all depends. It depends on how big your board advantage is. If I have three threats in play but only 1 card in hand, and my opponent has 4 cards in hand, based on this board state, I am way ahead in tempo and actually fairly equal in card advantage. 4 cards versus 4 cards, but a bunch of mine are in play. If it turns out I'm against a control deck and they start dropping huge guys that takes multiple resources for me to deal with, or he flamestrikes my board for a nice 3-for-1 trade for him, then the pendulum swings back to my opponent and I'm likely at the disadvantage card-wise. I think Card advantage as a concept is extremely fluid and can change on a dime.