Honestly, the answer to that depends so much on the deck contents it's hard to give a hard rule. I'll try to give some general guidelines on how I do it, though.
-In a duo, I will almost always use the mark of one type, and then pillars/pendulums all of the other type. This is to ensure that you will always have both types of quanta to start. (unless you have the supreme misfortune of drawing 0 quanta to start :p)
-In a duo, if my off element cards are very few and very cheap, I will just run them solely off the mark. This is a hard thing to judge sometimes, but for instance here is an old league deck that illustrates this:
Because the deck only uses 12 aether quanta maximum, and it is a slower deck, I use only death pillars.
Here is another example of a deck that uses even less of the off-element quanta:
However, it should be mentioned that decks with this kind of quanta base usually get owned by devourers or discords, because even a slight disruption in how the quanta is produced means you can lose a lot of tempo and fall far behind in the game because you can't play things as fast. This is a risk you take with such a deck; all decks will have some vulnerability or other.
Here is a deck where the quanta used is a lot closer to 50/50:
The deck is designed to produce more fire quanta because the firebolts and fahrenheits are perfectly okay with excess fire quanta, and the red nymphs use up a lot of quanta. Conversely, less death quanta is needed, particularly if you can keep one bone wall growing with bolts or nymphs and don't have to play the others. However, it is still capable of producing enough death quanta to play multiple bone walls if necessary. In the long run, it will overproduce death quanta, despite having more fire quanta generation, because the fire cards use up more. However, in the short term, you need to have lots of death quanta to get those bone walls out in the first place. Bone walls (and everything else) suck if you can't play them!
Here's an interesting case. In this deck, both water and earth are used fairly heavily, and in roughly equal proportions. How did I decide whether to use pendulums or pillars and what mark to use? (I didn't simply flip a coin :p) I looked at a typical opening hand for this deck and how the quanta would be produced in the first few turns. I have twelve one earth quanta cost cards, and nine three quanta water cost cards in this deck. Now, there are a few ways we could run the quanta in this deck:
A) mark of earth, lots of water pends
B) mark of water, lots of earth pends
C) mark of earth, lots of water pillars
D) mark of water, lots of earth pillars
E) mark of earth, split between water pillars/pends
F) mark of water, split between earth pillars/pends
We could also do other types of splits, like 2 water pend, 2 earth pend, 2 water pillar, 2 earth pillar, but remember above I said that in duos I normally like to have the mark produce one type of quanta and all of the quanta cards produce the other type, so that you always have both types right away. Therefore, based on this recommendation, I will throw away all the other combinations.
Now, I don't know whether you've read about QI (quanta index) yet, but basically, it's a measure of how much of each type of quanta a deck uses, by counting out the demand for each quanta and using that to determine the number of pillars. In this deck, there are twelve 1
cards, six of those have an ability cost of 1
, there are two 2
cards and nine 3
cards. Three of those water cards (squid) have an ability that costs 2
, and two of those water cards have an ability that costs 3
(trident). QI adds all the casting costs up in each element, and then adds twice the cost of the activated abilities. In this case, earth adds up to 30
(6+6+6x2+3x2) and water adds up to 37
(4 + 9 + 6 + 12 + 3x2). That should imply we need more water than earth, right?
Well... no. How many tridents are you going to play in one game? One maximum, unless something bad happens to it. How many shards of patience? One most likely, again, unless something bad happens to it. You can't assume they will -never- be destroyed (our opponent isn't going to let us win!) but we can probably drop a couple of these from the overall cost. For simplicity's sake in the math, I assumed that you could save 7
based on this concept of not needing to play ALL of the tridents/SoPs, so that it was an even 50/50 split for quanta actually used. (the redundant copies are still necessary in order to draw them more often, however; you cannot run this deck with one shard of patience, for instance)
So okay, we're assuming the deck uses the same amount of earth and water quanta here, which is pretty close to the truth. (and good enough for me) That means we probably want to use mostly/all pendulums, since they produce quanta in 50/50 proportion. Therefore, we will consider only choices A and B, and ignore the rest, because they will overproduce one type of quanta and underproduce the other. Also remember, however, that the mark itself produces quanta, exactly one pillar's worth, so the quanta production will be weighted in favour of the mark's element if we use all pendulums.
But wait... we have other quanta sources! There are gnome riders here; they make earth quanta. Wouldn't that mean that we should use a mark of water to balance it out with those? Well, as it turns out, yes, that is a good idea. However, while this is true, it misses the biggest reason that I used earth pendulums and a mark of water instead of the other way around.
The reason is like this. Imagine how your first few turns will play out.
1 water pendulum + earth mark to start: Play it. Turn 1 you get 1 water quanta and 1 earth quanta. Okay. What can we do on turn 2? Either a gnome or a warden if we have it. Okay, then we produce two earth quanta. What can we do on turn 3? 1-2 gnomes/wardens, if we still have any, then we produce one water quanta and one earth quanta, and quite possibly some more earth from gnome(s). What can we do on turn 4? Well, we still only have two water quanta, but we have lots of earth quanta. We've probably played all our earth cards out of hand by now, we haven't gotten our trident out yet (we didn't get 3 water) and so the only thing we have to do is use our wardens. Oh, but that kind of sucks, because there's no shard of patience growing them yet. What do we make at the end of turn 4? Well poop, we made 2 earth quanta, just what we didn't need...
Okay, so that sucked. But there was only one pendulum, which isn't very good. Fine; let's assume we got two of them to start.
2 water pendulum + earth mark to start: Turn 1 we play them, make 2 water quanta and 1 earth quanta. Turn 2 what can we do... it's exactly the same, except we can play a purify, if we got one. However, that's very unlikely to be relevant on turn 2. Okay, so we play a gnome or warden then, and then we make three earth quanta. What do we do on turn 3? Well, we can play up to three of our one quanta earth cards, but we probably don't have that many left; in any event, it's pretty safe to assume we can play any that we do have left. We still have only two water quanta, and likely no need of any purify we might have. Then we make 2 water quanta and one earth quanta. (plus gnomes, if any) Turn 4 we have 4 water quanta, and we can finally play one of our water cards! Yay!
3 water pendulum + earth mark to start: Awesome! Turn 1 we play 3 water pendulum, get 3 water and 1 earth. Turn 2, huzzah! We can play one of our 3 cost water cards and one of our 1 earth cards, and we have lots of both, so odds are great we have one of each. Then we make 4 earth quanta. Turn 3, if we have a trident or a warden, we can use that, but other than the rest of our 1 earth cost drops, we have nothing else to do.
(if you do 4 water pends to start, you'll find it takes just as long to do anything with water, and earth won't help. 5 will let you use a squid on turn 3... but with only 8 pendulums in the deck, you probably won't get 5 to start, and even if you do, that's only 2-3 cards left to see a squid in. Heck, you probably won't even get 4)
Alright, let's look at earth pendulums and mark of water now.
1 earth pend + mark of water start: Turn 1, 1 earth + 1 water quanta, turn 2, play a 1 cost earth card, just like the 1 water pend/earthmark case, but at the end of turn 2, we make 2 water quanta, for a total of 3. We also make 1 earth quanta if we played a gnome. Now look at turn 3. We have 3 water quanta for one of the water cards. When we used water pends and earth mark, we needed at least 3 pendulums in the opening hand to get that. With earth pends and water mark, we only need one! Plus, if we played a gnome on turn 2, well, now on turn 3, we can play another one of the one cost earth cards! That's way faster than the water pend/earth mark case was. A 1 earth pend/mark of water start is faster than a 2 water pend/mark of earth start, and comparable to a 3 water pend/mark of earth start in speed.
Given that, it should be obvious that 2-3 earth pends to start is even better. It should also be obvious that even a one earth pend start isn't a catastrophe in this deck due to the casting costs, since you can still get cards out in the first few turns, whereas a one water pend start with an earth mark in this deck is a disaster. Because of this, I was able to get away with only eight earth pendulums in the deck; I'm perfectly satisfied with only 1-2 in the opening hand, and that lets me use more nonquanta cards that I can still play, because they're all really cheap.
Still don't believe me/have no effing clue what I'm trying to say? Make the same deck, play ten games with all earth pends and a water mark, and play ten games with all water pends and an earth mark. I guarantee you'll notice a difference in how well the earth pend version does over the water pend version.
Now, how do you come up with that in the first place? What magical formula did I use? Trial and error and experience, I suppose. I used this deck as my (by far) longest example because I put a great deal of work into designing it, whereas all of the other decks in this post (except the trio) were originally literally slapped together in like 30 seconds.
Trios)
Trios are -much- harder to balance. As a result, competitive trios are quite rare, and it's hard to make even casual ones playable enough to be fun. Here's one of my favourites:
Even though water only has eight cards, because I absolutely -need- the nymph's tears in this deck to do much of anything, I make my mark water and use pendulums of the rest. That way, I can be assured of casting a nymph's tears fairly early if I have one, and if I only have one type of pendulum to start, I can still do stuff. There's really no hard and fast rule for trio balancing, except that it's freaking hard :p As a very loose rule of thumb, I prefer to do it as above, where I have the mark of one type, and then two types of pendulums (or, depending on the amount of quanta needed, those pendulums might be pillars instead; for instance, if nymph's tears cost 1 water quanta for some ridiculous reason, then pillars should be used instead of pendulums, because only a very small amount of water quanta would be needed, and the mark of water would be enough for all the water cards)]
Well, that was longer than it needed to be; been awhile since I made a post longer than like two sentences :p Hope it helped...