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Mystic Scry Buff + Rending: why the best choice depends on what you already rolled

Mystic Scry Buff is the calculator's name for an attack-dice ability that, in the Roll Attack Dice step of a shoot, fight, or retaliation, lets you either retain one of your fails as a normal success, or retain one of your normal successes as a critical success. You pick one, each time you attack. In-game it's the "Mystic Scry" ability.

A single "or" hides a real decision. The two options do different things, and which one is better is not fixed — it depends on the weapon's damage and on the rest of the dice you rolled. This note walks through why, and how the calculator resolves it.

The basic choice: one more hit, or one better hit

Ignore other abilities for a moment. Relative to the dice you rolled:

So the crit upgrade beats the extra hit exactly whencritDmg + Devastating > 2 × normDmg. Most KT2024 weapons sit just below that line, so adding a hit usually wins — until Devastating or a big crit-damage spike tips it over:

Better option in isolation (no other abilities)
Norm dmgCrit dmgDevastatingCrit value2 × normTake
34046fail → norm
34266tie → crit
34376norm → crit
25054norm → crit

(On an exact tie the calculator takes the crit. A crit and an equal-value pile of norms are not really interchangeable: the crit's Devastating portion ignores saves, a crit triggers Piercing, and one big hit loses less to Feel No Pain than two small ones. More on that below.)

Rending changes the answer — in both directions

Rending lets you upgrade one rolled norm to a crit if you already have at least one crit. That conditional is what makes Mystic Scry Buff interesting: the option you pick changes what Rending can do afterward, so the right pick flips depending on whether you already rolled a crit. Both of the following use the same weapon (norm 3, crit 4, no Devastating), where the isolated rule from the table above says "add a hit."

Case A — no crit yet: seed one so Rending can fire

You rolled {0 crit, 2 norm} with Rending. There is no fail to convert, so the choice is "upgrade a norm" vs "do nothing":

{0c, 2n}, Rending, norm 3 / crit 4
OptionAfter the buffAfter RendingDamage
Norm → crit1 crit, 1 norm2 crit, 0 norm8
Decline0 crit, 2 norm0 crit, 2 norm (Rending can't fire)6

Taking the crit looks weak in isolation (crit value 4 < 2 × 3), but it seeds the first crit, which then lets Rending promote the remaining norm for free. One buff becomes two upgrades: {2c, 0n} = 8, versus 6 for leaving the dice alone.

Case B — already have a crit: feed Rending a norm instead

You rolled {1 crit, 1 norm, 1 fail} with Rending. Now all three matter:

{1c, 1n, 1f}, Rending, norm 3 / crit 4
OptionAfter the buffAfter RendingDamage
Norm → crit2 crit, 0 norm2 crit, 0 norm (no norm to promote)8
Fail → norm1 crit, 2 norm2 crit, 1 norm11

Here you should not take the crit. You already have one, so Rending will hand you a crit regardless — provided a norm survives for it to promote. Spending the buff to add a norm gives Rending something to work on, ending at {2c, 1n} = 11. Spending it on a crit consumes the very norm Rending wanted, stalling at {2c, 0n} = 8.

Same weapon, opposite decision — driven entirely by whether you had already rolled a crit. A fixed rule ("always take the crit" or "always add a hit") gets one of these two cases wrong.

How the calculator decides

Rather than a fixed rule, the calculator treats Mystic Scry Buff as the per-roll choice it actually is. For every possible dice result it:

  1. builds the candidate outcomes — fail→norm, norm→crit, and declining;
  2. runs each candidate through the rest of the Roll Attack Dice step — notably Rending, then a defender's Obscured if present;
  3. scores each finished outcome by pre-save damage (crits × (critDmg + Devastating) + norms × normDmg) and keeps the highest, breaking ties toward the crit.

Because the score is taken after Rending resolves, the seed-vs-feed reasoning above falls out automatically — the calculator does not need to special-case it. The same mechanism handles Obscured: when the defender turns your crits into norms, a norm→crit upgrade gains nothing, so the comparison naturally prefers adding a hit.

What the choice does not weigh

The comparison is pre-save damage, so two things are deliberately left out:

Devastating (mwx) is counted — it is folded into the crit's value, so a weapon with meaningful Devastating will favor the crit upgrade, as the first table shows.

Take-aways

  1. On its own, the crit upgrade beats the extra hit only whencritDmg + Devastating > 2 × normDmg; otherwise add a hit.
  2. With Rending, that rule can invert. With no crit yet, seeding a crit can unlock a second upgrade from Rending. With a crit already in hand, Rending will promote a norm for you, so the buff is better spent keeping a norm alive for it.
  3. The calculator resolves the choice by trying every option through the remaining steps and keeping the most damage, so Rending and Obscured interactions are handled without a fixed rule.
  4. The choice maximizes pre-save damage; saves and Piercing are not weighed, beyond breaking exact ties toward the crit.

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