Ars 'n Spells

[2.5.0] — 1.21.1 compatibility & correctness (2026-06-06)

A correctness-focused compatibility release on top of the build-verified 2.0.1 core. The bridge / cross-casting / progression / resonance / rituals stack is unchanged; this release fixes the largest parity gaps, restores two silently-broken datapack features, and hardens optional-mod handling. Compile targets stay pinned to the build-verified Ars Nouveau 5.11.1 / Iron's Spellbooks 3.15.6; the target pack runs AN 5.11.7 / ISS 3.16.0 at runtime (event- and registry-based code tolerates the delta — see Known limitations). Build- and test-verified; in-game runtime validation remains pending (the build environment runs no Minecraft).

Fixed — datapack paths (were build-green but runtime-broken)

• Ritual recipes are obtainable again. The Spell Transcription / Uninscription apparatus recipes shipped under the 1.20.1 plural path data/ars_n_spells/recipes/…, which Minecraft 1.21 no longer reads (it loads recipe/, singular — verified against the Ars Nouveau and Iron's jars). They never loaded, so the ritual tablets were uncraftable in survival. Moved to data/ars_n_spells/recipe/apparatus/.
• Ritual recipes now parse. Once relocated, the same apparatus recipes surfaced a second carryover — the 1.20.1 recipe schema (output/item, reagent as an array), which fails AN's current enchanting_apparatus codec with No key result. Migrated to the 1.21 form (result with id+count, reagent as a single object); verified against the live pack (AN 5.11.7) so the Transcription/Uninscription tablets craft at the Enchanting Apparatus. A ResourcePresenceTest schema check now guards the format.
• Curio spell discount works again. The #ars_n_spells:curio_spell_discount item tag shipped at the plural tags/items/ path (1.20.1) instead of 1.21's tags/item/, so it never loaded and the discount was permanently inert. Moved to tags/item/, and the tag now ships a sensible default (#irons_spellbooks:school_focus, optional).

Added / changed — affinity now covers every Iron's addon school

• Dynamic, addon-aware affinity. Affinity was keyed by a hardcoded 16-value AffinityType enum, so the ~19 addon schools in the target pack (cataclysm_spellbooks:abyssal, iss_magicfromtheeast:spirit, somakespells:aqua, …) earned no affinity at all — the Iron's handler dropped every school not in the enum. Affinity is now stored as a Map<String,Integer> keyed by the full school id (mirroring progression), so every registered Iron's school tracks automatically, with no per-mod code. New SchoolKeys (the single canonical-key source shared by both handlers and the damage-scaling site) and an Iron's-gated SchoolIndex registry snapshot for /ans diagnostics.
• Fixed the mirrored Ars-side drop bug. aqua/geo/wind (words the Ars glyph heuristic emits but the enum lacked) threw in AffinityType.valueOf and were silently lost; they now track under ars_n_spells:* keys.
• Safe save migration. AffinityData uses a versioned codec; a 2.0.x save (bare map of enum-name keys) migrates losslessly — the nine elemental tracks are renamed (FIRE → irons_spellbooks:fire) with counts intact and re-stamped on first save (idempotent). Owner decision (default): the seven legacy category/source buckets (OFFENSIVE/DEFENSIVE/UTILITY/MOVEMENT/ARCANE/PRIMAL/HYBRID) are dropped on migration — they were never real schools and current code never wrote them. Back up saves if you want to be cautious; flip to quarantine on request.
• /ans info <player> now lists the player's non-zero affinity tracks and (with Iron's) the registered school count.

Added — Curios discount, both sides

• The tagged-curio mana discount now applies to Iron's casts too (SpellOnCastEvent.setManaCost), not just Ars casts. The slot scan is shared via a new compat/curios/CuriosAccess. New max_total_curio_discount config (default 0.50) caps the combined discount so stacked curios can't trivialise mana cost.

Hardened — optional-mod & version resilience

• All mana/resolver mixin injects now carry require = 0, so an Ars/Iron's point-release method-signature change fails soft (skips the inject) instead of crashing mod load. The mixin plugin additionally probes the Ars target classes (ManaCap/ManaData/ SpellResolver) so a class rename also fails soft. (Shadow field drift remains fatal — the eventual event-first migration is the real fix; see Known limitations.)
• New compat.ModPresence (cached multi-mod presence) + compat.CompatIds; IronsCompat delegates to them. Lightweight foundation; the full module framework is deferred.
• New #ars_n_spells:magical_companions entity-type tag (aggregates #ars_nouveau:familiar
  • #irons_spellbooks:summons, optional) as datapack scaffolding for future summon synergy.

Tests

• ResourcePresenceTest asserts every shipped data/asset file exists, parses, and sits at the correct singular 1.21 path (regression guard for the directory-flattening bug above).
• SchoolKeysTest pins the Ars↔Iron's key agreement and the aqua/geo/wind fix.
• AffinityDataMigrationTest covers the versioned codec round-trip and the 2.0.x → 2.5.0 legacy migration (rename, bucket drop, re-stamp, clamp).

Known limitations

• Compile vs runtime version delta. Pinned to AN 5.11.1 / ISS 3.15.6; pack runs 5.11.7 / 3.16.0. A post-2.5.0 task is to validate in-game and optionally move the compile classpath up. Mixin shadow-field drift (e.g. an AN field rename) would still crash on load — require = 0 covers method drift only; migrating the mana bridge to AN/ISS events is the durable fix and is deferred.
• In-game validation pending (build env has no Minecraft): cast one spell per addon school → affinity increments under the correct id; load a 2.0.x save → elemental tracks migrate with counts intact, buckets dropped; tagged-curio cast drops cost on both Ars and Iron's within the clamp; client + dedicated-server boot with/without Iron's and Curios; ritual tablets craftable at the apparatus.
• Covenant LP / aura / virtue / blasphemy remain N/A (Branch B). The dead Covenant config keys are intentionally retained to match the canonical 2.0.1 config.