Once you've found your hero's strongest cards, the rest of the deck is about filling the gaps efficiently. Three questions do most of that work: what does my resource curve look like, how many blues do I run, and what glue holds the deck together?
Building a resource curve
Blue cards pitch for 3 resources, and blues are the resource card of choice for most heroes. Unspent resource points disappear at the end of the turn, so any resource you generate and don't use is thrown away. A well-built deck is one where the cards in your hand consistently consume every resource you pitch, off just one or two pitched cards.
That means your card costs need to combine cleanly. One 3-cost card uses a blue exactly. So do three 1-cost cards. So does a 1-cost card plus a weapon activation that costs 2. What doesn't work is a hand full of 2-cost cards with nothing to soak up the leftover resource each time.
The catch is that resources aren't the only limit. Playing three cheap cards in one turn takes three action points, and you only start with one. So a hero with easy access to go again can build around 1-cost and 2-cost cards, while a hero without it is better off playing a single expensive card per turn. Two heroes can want completely different curves for that reason alone, even with the same resource math available.
Two more things shift the curve. Weapon and equipment activation costs are resource sinks like any card cost, so they belong in your calculation from the start. And some heroes are built to pitch yellows instead of blues, because a weapon or ability rewards them for it, which reshapes the whole curve around 2s and 4s rather than 3s and 6s.
The practical exercise: list the costs of every card you're considering, then check whether they combine into your pitch values given the number of action points you'll realistically have. Gaps in that math are where your remaining deck slots should go.
How many blues should you play?
This is one of the most common deckbuilding questions, and the answer is partly statistics and partly feel. Two things drive it: how many blues your strongest plays require to set up, and how many blues you need per hand on average to keep spending your resources efficiently.
Turning that into a deck count is simple division. With a 4-card hand and a 60-card deck, needing one blue per hand means roughly a quarter of your deck should be blue, so around 15. Needing two per hand doubles that to around 30. Start there and adjust.
Emphasis on start. Any number you reach this way is a first draft that testing will move, so treat it as something to play with rather than a rule.
What pushes your blue count up or down
Blues are a trade-off. Every blue you add makes your resources more consistent and your offense slightly weaker, since high pitch value usually means lower power. Two things soften that trade-off and let you play more of them.
The first is having blues that still do real work on offense. Some heroes have access to blue cards that hit hard enough to be worth playing rather than pitching, so a hand full of blues isn't a wasted turn.
The second is having resource sinks: equipment or abilities that convert spare resources into value. When leftover resources always have somewhere to go, generating too many of them stops being a problem.
There's a separate reason to raise the count. If your deck genuinely needs one or two blues in hand to function at all, run more than the math alone suggests. The cost of a non-functional hand is far worse than the cost of a slightly weak one.
One last pattern worth knowing: decks at the extremes tend to outperform decks in the middle. A very low blue count or a very high one both give you predictable hands, since you know roughly what you're drawing. A deck sitting in between draws blue-heavy hands and blue-light hands in equal measure and has to play around both. If your hero can be built toward one of the two extremes, that direction is usually worth testing first.
Adding glue cards and consistency
The strongest decks aren't strong because every card in them is a bomb. They're strong because they're consistent, and consistency comes from redundancy: having several cards that do more or less the same job, so you draw one of them most turns.
These are the glue pieces. They don't beat rate the way a power play does and they wouldn't impress anyone in isolation. What they do is make sure your gameplan comes together reliably. They fill two kinds of gaps at once.
The first is your resource curve. Once you know which costs your deck wants, you need enough cards at those costs that a typical hand contains them.
The second is your gameplan. Whatever condition your hero's ability needs met, whether that's filling a graveyard, generating tokens or setting up a specific state on your opponent, you need multiple ways to get there. One enabler isn't enough, because you won't draw it often enough to build a turn around it.
The best glue does both at once. A card that sits at the right cost, defends for 3 and also advances your hero's condition is worth more than its numbers suggest, because it's never a dead draw. Look for cards that check two boxes rather than cards that do one thing well.
A useful way to test a draft list: imagine three or four random hands from it. If most of them let you execute your gameplan, your glue is doing its job. If your good turns depend on drawing one specific card, you need more redundancy, not more power.
Source: https://fabtcg.com/articles/masterclass-deckbuilding/
