Chapter 54 — Companion Interception

54 — Companion Interception

Companion interception determines whether an ally steps in to absorb an attack aimed at a protected target (the player or a backline entity). The scored formula replaces the old flat 20 + instinct * 2 with a multi-factor calculation driven by reaction speed, composure, health, morale, combat state, and role.

When Interception Fires

An attack hits and damage is calculated.
The target qualifies for interception (player, or backline when engagement-core is loaded).
Eligible allies in the same zone are checked in order. An ally is eligible when: alive, same zone, isAlly() returns true, not FLEEING, and either ENGAGED or the target is the player.
Each ally rolls against their interception chance. First ally to pass absorbs the damage.

Scored Formula

defaultInterceptChance(ally, target, world, statMapping)

Component	Formula	Range
Base	`8`	fixed
Reaction speed	`floor(instinct * 2.5)`	0-25
Composure	`max(0, floor((will - 3) * 1.5))`	0+
Health	`floor(hpRatio * 8)`	0-8
Critical HP	`-15` when HP < 25%	0 or -15
Morale	`floor((morale - 50) * 0.15)`	-7 to +6
FLEEING	hard block (returns 0)	0
OFF_BALANCE	`-10`	0 or -10
GUARDED	`+8`	0 or +8
Role bonus	per-tag table below	-12 to +15
Clamp	`max(5, min(90, total))`	5-90

At default stats (instinct=5, will=3, full HP, morale=70, no status, no role), the formula produces 31% — within 1 point of the old flat 30%.

Role Bonuses

Tag	Bonus	Rationale
`role:bodyguard`	+15	Dedicated protector
`role:sentinel`	+8	Defensive specialist
`role:brute`	+5	Physically imposing
`role:elite`	+5	Trained fighter
`companion:fighter`	+8	Combat companion
`role:minion`	-5	Expendable
`companion:scout`	-5	Not built for tanking
`companion:smuggler`	-5	Self-preservation instinct
`role:skirmisher`	-8	Hit-and-run style
`companion:healer`	-8	Avoids frontline
`role:backliner`	-10	Stays behind
`companion:diplomat`	-10	Non-combatant
`companion:scholar`	-10	Non-combatant
`role:coward`	-12	Self-preserving

Combat role tags (role:*) take priority over companion tags (companion:*). If neither is present, the role bonus is 0.

Balance Tables

Factor variations from baseline (instinct=5, will=3, full HP, morale=70):

Scenario	Old	New
Baseline	30	31
instinct=7	34	36
instinct=10	40	44
will=5	30	34
HP=50%	30	27
HP < 25% (critical)	30	9
morale=30	30	25
morale=90	30	37
FLEEING	30	0
OFF_BALANCE	30	21
GUARDED	30	39
role:bodyguard	30	46
role:coward	30	19

Extreme combinations:

Scenario	Chance
Bodyguard, guarded, will=6, morale=90, instinct=7	72
Coward, half HP, morale=20, OFF_BALANCE	5 (clamp)

FLEEING Hard Block

A FLEEING ally never intercepts. This is enforced in two places:

Ally eligibility filter — FLEEING allies are excluded before rolling.
Formula — returns 0 if the ally has FLEEING status (defense in depth).

Engagement Integration

When engagement-core is loaded, withEngagement() wraps the formula:

PROTECTED targets get an additional +15 to their allies’ interception chance.
The wrapper calls defaultInterceptChance (not a flat fallback).
Total is clamped to [5, 90].

Narration

The combat-state-narration module listens for combat.companion.intercepted and generates narrator-channel text:

Standard: “steps in front of {target}, taking the blow”
Heroic (HP < 30% before interception): “staggers forward to shield {target}, barely standing”

Heroic interceptions get priority: 'high'.

AI Cover Awareness

The combat intent scorer estimates interception cover for each enemy:

Allies with role:bodyguard or role:sentinel contribute 15 cover.
role:brute or role:elite contribute 8.
role:coward or role:backliner contribute 2.
Default allies contribute 5.
FLEEING allies are excluded.

The AI applies a penalty of -min(10, floor(cover * 0.6)) to attack scores against well-covered targets, preferring to target enemies with weaker interception support.

Override

Pack authors can fully replace the interception formula:

createCombatCore({
  interceptChance: (ally, target, world) => {
    // Custom logic
    return 50;
  },
});

When interceptChance is provided, the default scored formula is bypassed entirely. The engagement-core PROTECTED bonus still stacks on top.

Pack Author Guidance

To create companion archetypes with distinct interception behavior:

# Loyal bodyguard — high interception, protects at all costs
entities:
  - id: iron-shield
    tags: [ally, role:bodyguard]
    stats: { vigor: 6, instinct: 7, will: 5 }
    # Interception: ~60% (bodyguard + high instinct + high will)

# Scholar companion — avoids frontline, rarely intercepts
  - id: sage
    tags: [ally, companion:scholar]
    stats: { vigor: 3, instinct: 4, will: 6 }
    # Interception: ~14% (scholar penalty + low instinct)

# Wounded veteran — intercepts heroically at low HP
  - id: old-knight
    tags: [ally, role:sentinel]
    stats: { vigor: 5, instinct: 5, will: 7 }
    # At full HP: ~45%. At critical HP: heroic narration fires.