Phased plan for the class-balance pass. Unlike the race pass, classes are *measured* not modeled: combat is one-shot auto-resolved through a seedable simulateCombatWithRNG, so the harness runs Monte Carlo over the real engine and reads win rates directly. Scopes the full matrix (10 classes × 30 subclasses × level checkpoints × monster tiers), the two hard policies to de-risk in Phase 0 (equipment loadout, spell selection), the per-tier win-rate parity rule, and the tuning levers. Phase 0 spike in progress.
4.7 KiB
GogoBee — D&D Class Balance Pass
Companion to:
gogobee_dnd_design_doc_v1.1.md,gogobee_spell_system.md,gogobee_subclass_system.mdVersion: 0.1 (planning draft) Status: Pre-implementation — Phase 0 spike in progress Sibling work: the race-balance pass (internal/plugin/dnd_race_balance.go,TestRaceBalance) — same spirit, different method (see §1).
0. Why this doc exists
The race-balance pass tuned the seven races to equal effective power via a hand-weighted scoring model. That model is a proxy — races don't fight, so there is nothing to measure directly.
Classes are different: combat is one-shot auto-resolved through a single
simulateCombatWithRNG call (combat_engine.go:338), and the RNG is
seedable. So class balance does not need a proxy model — we can run
thousands of real, reproducible fights and read the win rates directly.
This doc plans that work. Endgame: a TestClassBalance regression fixture that
holds per-tier win-rate parity across all 10 classes × 30 subclasses, plus the
tuning pass that gets us there.
Non-goals. Not a combat-engine redesign. Not adding classes/subclasses. "Balanced" means balanced in gogobee's one-shot engine — the model collapses tabletop action economy, and that is accepted.
1. Method — measure, don't model
| Race pass | Class pass | |
|---|---|---|
| Power source | ability mods only | full combat: HP/AC, weapons, spells, passives, subclass tiers |
| Approach | hand-weighted scoring proxy | Monte Carlo over the real engine |
| Trust | heuristic weights (estimated) | empirical win rates (measured) |
| Artifact | dnd_race_balance.go + TestRaceBalance |
dnd_class_balance.go + TestClassBalance |
2. The matrix (full)
For each of the 10 classes:
subclass = noneat L1–L4- each of its 5 subclasses at the L5 / L7 / L10 / L15 / L20 tier-unlock checkpoints
→ ~60 build profiles × level checkpoints × ~6 monster tiers. Each cell = N
seeded fights through simulateCombatWithRNG. One-shot sims are cheap; compute
is not the constraint.
Opponents: the existing per-tier monster scaling curves
(dnd_combat.go:35–51) — dungeon Tier and arena ThreatLevel — used as a fixed
gauntlet.
Builds: standard array assigned by each class's stat priority
(dnd_combat.go:185–218), Human race (neutral baseline, +1 all), plus a
standardized equipment loadout (see §3).
3. The two hard parts (Phase 0 de-risks these)
- Equipment loadout policy. Combat uses equipment-driven AC and real weapon dice. The per-class, per-level kit must be standardized fairly or every downstream number is garbage. Derive from existing starting-gear / level tables if they exist; otherwise define a canonical tiered kit.
- Spell-selection policy. Caster damage flows through
applyPendingCast. Without a "what would a player cast here" heuristic per class/level, all 8 casters fight as naked weapon-users and read as broken — a measurement artifact, not real imbalance.
4. Balance rule
Per-tier win-rate parity: at each difficulty tier, every class within a tolerance band of the cross-class mean win rate. Band set empirically after the first full run (the race pass's ±0.5 was set the same way). Damage-dealt, HP-remaining, and near-death-rate are logged as diagnostics, not asserted.
5. Phases (one phase ≈ one session; each ends green + committed)
- Phase 0 — spike. Harness skeleton; equipment + spell-selection policies; run Fighter vs. Mage only across tiers and sanity-check plausibility (both win something; casters not at 0%). If the numbers are implausible, fix the policies before trusting anything. ← current
- Phase 1 — harness + matrix. Generalize to all 10 classes × 30 subclasses;
TestClassBalancelogs the full report. No tuning yet — just measurement. - Phase 2 — tuning pass. Adjust the levers (class passives → subclass tiers → spell dice → AC floor → attack bonus, in that order) until the parity band holds. Lock the band into the test assertion.
- Phase 3 (if needed) — second-order. Subclass-vs-subclass spread within a class; the Paladin/Rogue MAD question if the data shows it bites.
6. Tuning levers (priority order)
- Class passives —
dnd_passives.go - Subclass L5/7/10/15 tiers —
dnd_subclass_combat.go - Spell damage dice & upcast —
dnd_spells_data.go,dnd_spells_srd_data.go - Spell slot progression —
dnd_spells.go - AC floor / armor proficiency —
dnd.go:164–178 - Attack bonus class matrix —
dnd_combat.go:22–33 - Monster scaling curves —
dnd_combat.go:35–51(last resort; affects PvE feel)