Art Data - Tactical Arts records Confirmed

Overview

Implementation: crates/art.

Where the data lives

Confidence: Inferred - citation chain comes from external RE work cross-referenced with Meth962's earlier observations; a watchpoint trace pinning the runtime read sites is still pending.

Action Constants

Every entry in the battle action queue is one of these 0x00–0x32 values:

The first 4 directional bytes of a Miracle Art's replacement string are stored on disc with the high nibble's MSB set (0x8C / 0x8D / 0x8E / 0x8F); the runtime ANDs with 0x7F when copying into the queue. legaia_art::miracle::unmask_replacement_byte matches that.

Art record layout

The layout is schema-then-walk: each record begins with a fixed prefix (commands, action constant, anim index), and the remainder is a sequence of variable-width fields whose presence depends on the art. The researcher captured field positions but did not pin every byte - this page documents the schema; crates/art ships a strict parser for the prefix and surfaces the unparsed tail for downstream tooling.

Fixed prefix

+0x00  u8[]   command sequence - values 1=L, 2=R, 3=D, 4=U; terminated by 0x00
       u8     action constant (0x1B..=0x32)
       u8     anim_index (primary)
       u8[5]  anim_extra (reserved; usually 0; some Hyper Arts chain multiple records)

Variable fields (positions documented, exact byte offsets per art-specific)

Power encoding

Concretely: 0x1D = LDF × 20, 0x19 = UDF × 22, 0x1F = LDF × 28, 0x1A = UDF × 28.

Learned Art Constant

A separate per-character byte (0x8008488D Vahn, 0x80084CA1 Noa, 0x8008506C Gala) tracks the highest learned art slot. Slot indices 0..=0x10 resolve to action constants through a per-character indirection table - and that table has holes: Noa skips slots 0x02 and 0x03 because her Hurricane Kick covers all three on-disc levels through a single learned slot.

Crate API: legaia_art::learned_art_action(character, slot) returns the action constant for a slot, or None for holes / out-of-range.

Vahn and Gala stop at 0x0E (15 learned arts each). Noa extends to 0x10 (15 learned arts but spread across 17 slot positions because of the two Hurricane Kick holes).

Art Anim Data

Selects the animation record played when the art fires. The Art Record's anim_index byte at offset +16 indexes a per-character animation table. Slot 0 is always Spirit; slot 3 is always Art Starter. Some slots are holes (e.g. Vahn has no slot 0x0C, Gala has no slot 0x09).

Crate API: legaia_art::art_anim_name(character, anim_index).

Most art records reference exactly one anim slot; a handful (e.g. Hurricane Kick on Noa) use the anim_extra reserved bytes at +17 to chain into a continuation slot for multi-stage animations.

Miracle Arts

Each character has one Miracle Art. When the player enters the exact command sequence for that art, the runtime clears the entire action queue and writes the art's replacement string instead.

Each replacement string follows the shape [L, R, D, U, SpecialStarter, art1, art2, ...] where the four leading directionals are the on-disc MSB-set bytes (0x8C/0x8D/0x8E/0x8F), masked to 0x0C/0x0D/0x0E/0x0F at copy time. The full table is in crates/art/src/miracle.rs.

Super Arts

Super Arts are not invoked by direct command-string match. Instead, after each art finishes, the runtime walks the full action queue and looks for a registered Find pattern. If a Find pattern matches the tail of the queue and all participating arts paid AP, the matched bytes are replaced by a Replace tail that ends with the Super Art's finisher action constant.

Example - Vahn's Tri-Somersault (0x2B):

Find:    19 27 0F 19 1F 0E 19 27
         (Starter Somersault Up Starter Cyclone Down Starter Somersault)
Replace: 19 27 0F 19 1F 0E 1A 2B 2B 2B
         (… SpecialStarter, Tri-Somersault × 3 hits)

Triggers:

1. The last art of the Find string must be the last action in the queue.
2. All arts in the Find string must be non-NEW (their AP cost is paid).
3. Super Arts themselves do not consume AP - the chain arts pay it.

Full per-character tables (5 entries each for Vahn / Noa / Gala = 15 total) are in crates/art/src/super_art.rs.

Arts-name table (DAT_80075EC4)

The display names + AP costs of every Tactical Art live in a static table in SCUS_942.54 at DAT_80075EC4. It's the table the MES interpreter's 0xC5 substitution code reads (see MES bytecode encoding) - the 0xC5 operand XX keys it as (character = XX>>6, art index = XX&0x3F).

The expander (FUN_80036514) scans 20-byte (0x14) records sorted by character, matching (record[+0], record[+1]) against the key, and returns the +0xC name pointer ((&PTR_DAT_80075ED0)[match_index * 5]).

A (99, 99) record named "End" terminates the table. Each character's index 0 entry is the Miracle Art (AP byte 99; the name string opens with a 0xCE 0x09 character-name-substitution control, e.g. "&'s Ark" / Gala's "Biron Rage").

The AP costs are byte-exact against the curated gamedata arts table (every matched art agrees), which makes this the on-disc provenance for that table's ap column + the canonical art display order.

Command-glyph string (+8)

The +8 pointer is the command-input display string - the arrow sequence shown in the arts menu, and an independent on-disc source for each art's directional command (the PROT 0x05C4 art-record command bytes are a best-effort parse pending a watchpoint). Encoding: [count u8] then count two-byte glyph codes. A one-off 0xFF XX marker separates the sequence (0xFF06 for regular arts, 0xFF09 for Miracle arts) and is not a direction. The arrow glyphs map to physical d-pad directions:

The string stores the physical direction; the logical action (Arms / Ra-Seru) depends on the character's handedness (Noa's Arms / Ra-Seru are swapped). The codes match the Left=1 / Right=2 / Down=3 / Up=4 encoding the PROT records use. Cross-checking against gamedata surfaces at least one walkthrough error (Vahn's Hyper Elbow is L R L on disc, not Arms / Ra-Seru / High). Decoded by legaia_art::arts_table::parse_from_scus; dump it with art arts-table.

Validation oracle

Because the glyph string is byte-exact ground truth, it serves as the validation oracle for the two derived command sources:

• The best-effort PROT 0x05C4 parser (legaia_art::parse_record). legaia_art::ArtsOracle::by_command(character, &commands) resolves a decoded command sequence back to a named art; the disc-gated contract test crates/art/tests/arts_table_real.rs runs every art's canonical record bytes through parse_record and asserts the decode round-trips through the oracle. This pins the parser's 1=L,2=R,3=D,4=U command-byte decode against the executable without needing the (still-unpinned) full record stride.
• The curated legaia-gamedata arts.toml ap + directions columns. The disc-gated test crates/gamedata/tests/arts_scus_oracle.rs matches each curated art to its SCUS row by name and asserts AP + directions agree, with a small explicit allowlist for documented walkthrough errors (currently only Hyper Elbow). A new undocumented divergence fails the test.

See also

• docs/subsystems/battle-action.md - battle action state machine that consumes the queue and resolves damage.
• docs/subsystems/battle-formulas.md - damage / MP / accuracy / RNG arithmetic kernels that read the power bytes.
• docs/formats/mdt.md - the per-frame animation bytecode for the Tactical Arts move VM, distinct from this art-record layer.