Each of your ratings is so precious: it is one step further towards a better "bottom-up" understanding of the set in Limited format.
The "top-up" view is often provided by WotC, if not obvious already, through each colour pairing (or triplet, or sometimes monocolor!) archetype. The signpost gold cards often give it away.
Over and above that, we believe here that there are several flavours of each single archetype, or even colour pairs which are leaning towards other game plans than the "official" ones. Practice makes perfect, arguably, but scrutinising the set early on could certainly unveil some of the hidden tracks leading to these alternative strategies.
By starting from each possible pair taken in a vacuum, we will build card-by-card relationships, which will evolve into clusters, to then get used as lists of compatible ingredients in the recipe for out-of-the-ordinary decks.
A set of 260 non-basic land cards like KDH makes ~34,000 unsorted pairings. Way more than a single person could process, let alone between when the last cards are spoiled and when we get to play with it. So we do indeed treasure each of your ratings!
The relationship between the 2 cards needs to be evaluated with some context. Below are a few points to consider, but right before that, here's a table that gives an summary of what's behind the 5 rating buttons, and the criteria to select your pick:
one-off, little impact on the board, such as a fulfilled condition to reduce the cost of a spell by 1 mana (e.g. for the Party mechanic in ZNR), or gaining a couple of life points
great, but very unlikely one-off event, such as reaching ultimating a PW
improvement on only one of the 2 cards of the pair
one-off, significant impact on the game, such as getting a 2-for-1
permanent, or small but repeatable benefit, such as consistently allowing triggers to gain some life, or giving permanently +1/+1 to a creature
not necessarily controllable trigger, such as leave-the-battlefield triggers
improvement on one or both cards of the pair, depending on the benefit
one-off impact on the board that turns the game around, such as a sweeper changed to be one-sided only
repeatable way to generate card advantage or reduce significantly opponent's life total, with mostly controllable trigger
significant permanent effect
improvement on both cards (2-way synergy)
same criteria as the game-changing advantage, at a level that it is almost impossible for your opponent to come back, such as an alternative and unavoidable win condition
NB: this is a rare case in Limited, to be used only on exceptional cases!
Here are additionally the assumptions that will affect the ratings:
Limited decks have 40 cards - they could have more, but let's stick to 40
they include 16 to 18 lands most of the time - to evaluate the probability of triggering/benefitting from land-related spells and abilities
they include 10 to 20 creatures - that's how most Limited games are won
In practical terms, it means for example that a non-basic land does not specifically generates a synergy with a landfall trigger; when assessing the impact of a landfall trigger, it's better to consider the probability to be able to trigger it. Similarly, Agadeem's Awakening (see below in the examples) doesn't get better when paired with whatever kind of creature, so it is not necessary to record any synergy in this case (it is relevant, however, for creatures which have an ETB that triggers when they get reanimated!).
The rating should reflect how better the cards become when they are around each other at the same time (e.g. in your hand, or in play, or in your graveyard sometimes), everything else aside. Whether the cards "belong" or not to the same archetype is irrelevant: on the contrary, we're trying to build new ones! We're not interested in curve issues (e.g. how well 2-drops go together in an aggro deck), nor colour issues (e.g. this RG gold card can make this BW card better - we will assess the impact of a sketchy mana base at a later stage). The improvement needs to be on pure face value.
The rating is undirected, meaning that we're considering the improvement of the pair of cards as a whole. It important to consider how the whole (both cards together) is more than the sum of its parts. For example, if one of the card has a dependency on a card type that is provided by the other card, the improvement rating should reflect that. For those of you who contributed to the rating process for ZNR, this is a change - hopefully for the better!
And to wrap up: yes, agreed, it is a bit subjective in the end! So to make up for that, we will be using the wisdom of the player community to pick up what could be the most appropriate rating. You might disagree (hopefully not completely!) with the explanation on the examples below, and would consider a different rating - and that's totally fine. With enough input, we will be able to check controversial pairs and make an assessment, maybe involving the community directly! So please feel free to rate according to your understanding of these context elements.
no additional benefit
These 2 cards are totally unrelated. In an aggressive deck, we could imagine some kind of benefit of bouncing part of the opponent's defense to clear the way for the Fireblade Charger to attack, but that's already considering a strategy over and above the pure face value of the cards.
NB: actually, the majority of the pairings are in this case - don't be concerned about choosing that rating most of the time!
no additional benefit
These 2 cards belong to different archetypes with little overlap, so putting them together seems counter-intuitive. But in strict terms, casting one while having the other in play won't make the latter feel any better or worse. They're not clashing, just not making each other more impactful.
no additional benefit
Agreed, Nimana Skitter-Sneak does provide a target to bring back from the graveyard if Agadeem's Awakening is played for 4BBB. However, the assessment of the value obtained for its casting cost against the probability of hitting targets in your graveyard was already made when rating Agadeem's Awakening in absolute terms. Nimana Skitter-Sneak doesn't change any of that. Conversely, the Awakening doesn't make the Sneak more interesting to play, it is just another 4-drop to bring back, with no ETB trigger.
small perk
If we get to attack twice this turn, neutralising a big blocker or a deathtoucher could help. That would be definitely a positive to point out, but it is a narrow case - much narrower than e.g. having a Wizard to draw a card. Hence, the small improvement - not an absolute 0!
small perk
Concerted Defense cares about having many members in the party, so the Scion of the Swarm being a Cleric does make it better. Not by a lot though.
NB: the Scion might fit better in the WB lifegain archetype, or the BG +1/+1 token archetype, rather than with U, but again, archetypes and high-level synergies are irrelevant for our review.
decent benefit
BG lifegain? It is not straight away advertised as an archetype, but there's definitely a synergy here. The repeatable trigger does improve the Nectarpot more than marginally.
game-changing advantage
Making Chatrix sneaking through a shortcut is unreasonably good. It does require you not to be too far behind on the board to afford tapping 2 blockers, and having a fair amount of mana available to pay for the activation costs, but given a few turns and no other surprise, you should be able to close the game.
game-changing advantage
Here's an example of a broken synergy, on cards which are respectively good or average individually, but in no way at bomb levels. First of all, the Healer makes the second part of the Vial's text relevant. So relevant, that when one Cat (created by the Healer) dies, then it get replaced by another one. Even if it only works with the first one of the turn. And to bring the combo to the bomb level, the Vial allows you to not only get value from having a Cat dying, but as well to control when you want it to happen. For example, after chump-blocking at attacker.
game-changing advantage
Sacrificing Linvala before casting the Inversion makes the Inversion a one-sided sweeper, with the immediate benefit of a free attack. You only need to have another decent body in play to finish the job.
winning combo
The math here should make the kicked Scourge's power higher than your opponent's life, and the Fury gives you an immediate finish. Beware of archetypes which play with lifegain though: it doesn't work if your opponent was above 20 life at the time you cast the kicked Scourge.
So by now you hopefully feel better about rating the pairings. Thanks for reading, and let us know about your feedback and ideas on the Forum page!