Lesson 10 · Durable Core

Slot-to-Bucket Mapping

Knowing which statistic is starved is only half a diagnosis. The other half is whether anywhere on the character can still supply it.

~12 minutes One-step arithmetic Pairs with the audit loop

Scope

Earlier lessons produce a diagnosis: this additive total is starved, this enemy-side term is empty. That diagnosis is only actionable if some slot can still carry the thing you need.

This lesson is about the supply side — which slots can carry which statistics, why the number of affixes on a character is a fixed budget, and how to recognise the situation where the thing you need has nowhere left to go.

1 · The affix budget is fixed and small

A rare item carries at most six explicit modifiers — three prefixes and three suffixes. Magic items carry two, one of each. Rare jewels are the exception at four, two of each.

A character wears roughly ten pieces of gear. That is on the order of sixty affix slots for the entire character, permanently, and every statistic you want competes for the same sixty.

Gear is not an open-ended source of statistics. It is a fixed number of slots, split into two separately-limited halves, and the split is what usually binds.

The prefix and suffix limits are separate. Filling all three prefixes on a chest does not make the fourth prefix available; it makes prefixes full while suffixes may still be open. Two items with the same number of useful modifiers can therefore have very different remaining capacity.

2 · Which half a statistic lives in

Broadly, per the wiki's own framing:

HalfTypically carries
Prefix Primary statistics — damage, life, mana, movement speed
Suffix Secondary statistics — resistances, accuracy, attributes

This produces a structural pressure worth stating plainly.

Resistances are suffixes, and resistances must be capped. Every character therefore spends a large fraction of a fixed suffix budget on a requirement it cannot negotiate — which makes suffix space the scarce half for most characters.

The consequence is that suffix-based statistics compete with a mandatory expense in a way prefix-based ones do not. When a character cannot find room for a suffix statistic it wants, the cause is usually resistances, and the remedy is usually to source resistance more efficiently rather than to abandon the statistic.

3 · Slots are not interchangeable

Each base type can roll only its own set of modifiers. Broad patterns, which should be verified against the actual item rather than trusted:

StatisticUsual homes
Flat added damageWeapons, rings, amulets, gloves
Attack or cast speedWeapons, gloves, boots
Movement speedBoots, almost exclusively
ResistancesNearly every slot
Life and energy shieldMost armour slots, plus jewellery
Critical statisticsWeapons, rings, amulets, gloves
Skill levelsAmulets and weapons
This table is the weakest thing in the lesson

No consolidated, maintained source for affix-availability-by-base exists for PoE2. The wiki carries per-base modifier tables but they are scattered and patch-sensitive. Treat the above as orientation, not authority, and confirm against the base you are actually holding.

The method in section 5 is durable. The table is not.

Note the asymmetry: movement speed has essentially one home, while resistances have almost every home. A statistic with one home is a hard constraint on that slot; a statistic with many homes is flexible and should be sourced wherever it is cheapest.

4 · The other supply lines

Gear is not the only source, and a statistic with no gear home may still be obtainable.

SourceSuppliesCost
Passive treeMostly increased percentages, rarely flatPoints, and travel distance
Support gemsMostly more multipliers and behaviourA socket
AscendancyEffects unavailable elsewhereDecided early, expensive to change
Runes and enchantmentsTargeted statistics into a socketA socket, and the rune
Buffs and aurasBroad effects while activeSpirit or mana reservation

These have different budgets. Being out of suffixes does not mean being out of sockets. The tree and gear are largely complementary: the tree supplies percentages, gear supplies flat values and resistances, and support gems supply the multipliers neither can.

Check

A character needs more flat added damage. Which source is least likely to supply it?

5 · The method

Given a statistic you have decided you need:

  1. Which half is it? Prefix or suffix. This determines which budget it draws on.
  2. Which slots can carry it? Read the bases, do not assume.
  3. Of those slots, which have room in the correct half? A slot with three useful prefixes and one suffix has room only for suffixes.
  4. If no slot has room, what would have to be displaced? Name it, and compare what you would lose against what you would gain.
  5. If nothing is worth displacing, check the other supply lines. Tree, sockets, runes, buffs — different budgets entirely.

The situation worth recognising: the statistic you need has no remaining home. That is not a reason to keep looking for items. It is a signal that the next improvement must come from a different supply line, or from displacing something.

Worked diagnostic

Diagnostic

A character has been diagnosed as needing more attack speed. Its gear:

Gloves
Rare
  • Adds 14 to 26 Physical Damage to Attacks
  • +72 to maximum Life
  • +38% to Cold Resistance
  • +31% to Chaos Resistance
Boots
Rare
  • 25% increased Movement Speed
  • +64 to maximum Life
  • +41% to Fire Resistance
  • +35% to Lightning Resistance

Resistances are exactly at cap with no surplus. Where does the attack speed come from?

Both slots are full in the half that matters. Attack speed on gloves and boots is a suffix, and both items carry two resistance suffixes. There is no open suffix on either.

Displacement would break the resistance cap. Removing a resistance suffix to make room drops a resistance below cap — and lesson 1 established that the final points of resistance are the most valuable, so that trade is almost certainly negative.

So the honest answer is that gloves and boots cannot supply it as they stand. The remaining routes, in rough order of cost:

  • Source resistance more efficiently elsewhere. If another slot could carry two resistances in place of something less valuable, a suffix frees up here. This is the usual real answer, and it is why suffix pressure is a whole-character problem rather than a per-slot one.
  • The weapon. Attack speed is local there, and local attack speed is multiplicative with global — so it does not join the additive total and is not diluted by it.
  • Other supply lines. Tree, support gems, runes, buffs — none of which draw on the gear suffix budget at all.

The general lesson: "I need attack speed" was not the actionable diagnosis. "I need a free suffix" was, and that reframes the problem from shopping for gloves to rebalancing where resistances live.

What to carry out of this