diff --git a/compatibility/compiler-expectations.json b/compatibility/compiler-expectations.json
index 479d7ee..eb3a29a 100644
--- a/compatibility/compiler-expectations.json
+++ b/compatibility/compiler-expectations.json
@@ -346,6 +346,20 @@
       "note": "The shared hudSubheader action lowers to canonical Create HUD Text WIR with the pinned argument order and visibility semantics.",
       "semanticEquivalent": true
     },
+    {
+      "fixture": "synthetic/issue-130-horizontal-facing-angle",
+      "nativeStatus": "success",
+      "classification": "match",
+      "comparison": "semantic-wir",
+      "evidence": [
+        "oracle:synthetic/issue-130-horizontal-facing-angle/oracle.json",
+        "provenance:synthetic/issue-130-horizontal-facing-angle/fixture.json",
+        "test:opy-rs::compiler::integration_tests::issue_130_horizontal_facing_angle::horizontal_facing_angle_member_matches_the_pinned_canonical_wir"
+      ],
+      "owner": "opy-rs#130",
+      "note": "The catalog-backed eventPlayer.getHorizontalFacingAngle() member value lowers to canonical WIR equivalent to the pinned oracle.",
+      "semanticEquivalent": true
+    },
     {
       "fixture": "synthetic/issue-131-spec-visibility",
       "nativeStatus": "success",
@@ -454,9 +468,9 @@
         "provenance:real-world/overpy-client-to-server/fixture.json"
       ],
       "owner": "opy-rs#88",
-      "note": "The chained ternary and isDummy regressions now lower; the full real-world project remains outside the #38 compiler baseline and currently stops at the next unsupported member (`getHorizontalFacingAngle`).",
+      "note": "The chained ternary, isDummy, and getHorizontalFacingAngle regressions now lower; the full real-world project remains outside the #38 compiler baseline and currently stops at the next unknown value (`horizontalAngleOfDirection`).",
       "failureClass": "frontend",
-      "diagnosticCode": "unknown-member"
+      "diagnosticCode": "unknown-value"
     },
     {
       "fixture": "real-world/overpy-cronch",
diff --git a/compatibility/differential-expectations.json b/compatibility/differential-expectations.json
index 7e0896f..0511a18 100644
--- a/compatibility/differential-expectations.json
+++ b/compatibility/differential-expectations.json
@@ -33,13 +33,14 @@
     {"fixture": "synthetic/chase-condition-agentlab", "nativeStatus": "success", "classification": "match", "ruleNames": true, "evidence": ["oracle:synthetic/chase-condition-agentlab/oracle.json", "regression:agent-lab-chase-condition-shape"], "note": "The agent-lab chase condition shape is retained as an OPY source implementation regression."},
     {"fixture": "synthetic/chase-keywords", "nativeStatus": "success", "classification": "match", "ruleNames": true, "evidence": ["oracle:synthetic/chase-keywords/oracle.json", "implementation-invariant:keyword-binding"], "note": "Generic keyword binding and the chase contextual form resolve."},
     {"fixture": "synthetic/for-range-agentlab", "nativeStatus": "success", "classification": "match", "ruleNames": true, "evidence": ["oracle:synthetic/for-range-agentlab/oracle.json", "regression:agent-lab-for-range-binder"], "note": "Implicit for-range binders are retained as an OPY source implementation regression."},
+    {"fixture": "synthetic/issue-130-horizontal-facing-angle", "nativeStatus": "success", "classification": "match", "ruleNames": true, "evidence": ["oracle:synthetic/issue-130-horizontal-facing-angle/oracle.json", "provenance:synthetic/issue-130-horizontal-facing-angle/fixture.json", "test:opy-rs::compiler::integration_tests::issue_130_horizontal_facing_angle::horizontal_facing_angle_member_matches_the_pinned_canonical_wir"], "note": "The catalog-backed eventPlayer.getHorizontalFacingAngle() member value resolves through the OPY manifest and matches the pinned canonical WIR."},
     {"fixture": "synthetic/diagnostics", "nativeStatus": "failure", "classification": "match", "ruleNames": false, "evidence": ["oracle:synthetic/diagnostics/oracle.json", "implementation-invariant:parse-error-code"], "note": "Malformed source must produce the stable parse-error diagnostic."},
     {"fixture": "real-world/overpy-cake", "nativeStatus": "success", "classification": "match", "ruleNames": true, "evidence": ["oracle:real-world/overpy-cake/oracle.json", "provenance:real-world/overpy-cake/fixture.json"], "note": "Pinned OverPy example resolves through the native OPY semantic model."},
     {"fixture": "real-world/overpy-pixelart", "nativeStatus": "success", "classification": "match", "ruleNames": false, "evidence": ["oracle:real-world/overpy-pixelart/oracle.json", "provenance:real-world/overpy-pixelart/fixture.json"], "note": "Pinned OverPy example resolves; emitted rule shape is not the contract."},
     {"fixture": "real-world/overpy-santa", "nativeStatus": "failure", "classification": "known-gap", "ruleNames": false, "evidence": ["oracle:real-world/overpy-santa/oracle.json", "regression:real-world/overpy-santa/fixture.json"], "note": "The player-variable range binder now resolves; the full project advances to the next unsupported multiline conditional expression at santa.opy:359."},
     {"fixture": "real-world/overpy-cronch", "nativeStatus": "failure", "classification": "known-gap", "ruleNames": false, "evidence": ["oracle:real-world/overpy-cronch/oracle.json", "regression:real-world/overpy-cronch/fixture.json"], "note": "The postfix increment regression now resolves; the full project reaches the next unsupported createDummy action at cronch.opy:103."},
     {"fixture": "real-world/overpy-broken-weapons", "nativeStatus": "failure", "classification": "known-gap", "ruleNames": false, "evidence": ["oracle:real-world/overpy-broken-weapons/oracle.json", "regression:real-world/overpy-broken-weapons/fixture.json"], "note": "The numeric-range setting regression now resolves; the full project advances to the next known native gap at `isAssemblingHeroes`."},
-    {"fixture": "real-world/overpy-client-to-server", "nativeStatus": "failure", "classification": "known-gap", "ruleNames": false, "evidence": ["oracle:real-world/overpy-client-to-server/oracle.json", "regression:real-world/overpy-client-to-server/fixture.json"], "note": "The chained ternary and isDummy regressions now resolve; the full project remains an explicit known gap at the next unsupported member (`getHorizontalFacingAngle`)."},
+    {"fixture": "real-world/overpy-client-to-server", "nativeStatus": "failure", "classification": "known-gap", "ruleNames": false, "evidence": ["oracle:real-world/overpy-client-to-server/oracle.json", "regression:real-world/overpy-client-to-server/fixture.json"], "note": "The chained ternary, isDummy, and getHorizontalFacingAngle regressions now resolve; the full project remains an explicit known gap at its next unsupported construct."},
     {"fixture": "real-world/overpy-crosshair", "nativeStatus": "failure", "classification": "known-gap", "ruleNames": false, "evidence": ["oracle:real-world/overpy-crosshair/oracle.json", "regression:real-world/overpy-crosshair/fixture.json"], "note": "The SpecVisibility.NEVER and hudSubheader boundaries now lower; the full project reaches the separate unsupported hudSubtext action."},
     {"fixture": "real-world/overpy-inputhud", "nativeStatus": "failure", "classification": "known-gap", "ruleNames": false, "evidence": ["oracle:real-world/overpy-inputhud/oracle.json", "regression:real-world/overpy-inputhud/fixture.json"], "note": "Implicit string concatenation now parses; the full project advances to the separate unsupported conditional-value expression gap."},
     {"fixture": "real-world/overpy-parabola", "nativeStatus": "failure", "classification": "known-gap", "ruleNames": false, "evidence": ["oracle:real-world/overpy-parabola/oracle.json", "regression:real-world/overpy-parabola/fixture.json"], "note": "The numeric enum member regression now resolves; the full project reaches the next multiline parenthesized expression gap at parabola.opy:50."},
diff --git a/compatibility/fixtures/README.md b/compatibility/fixtures/README.md
index a3d7bdf..38976b1 100644
--- a/compatibility/fixtures/README.md
+++ b/compatibility/fixtures/README.md
@@ -61,6 +61,7 @@ repository:
 | `issue-59-embedded-postfix-negative` | #59 pinned negative probe for the rejected embedded postfix form with a stable source-attributed parse diagnostic |
 | `issue-65-player-range` | #65 pinned oracle-backed player-variable range binder probe for canonical `For Player Variable` lowering |
 | `issue-65-invalid-binder` | #65 pinned negative probe for a non-variable range binder with a stable source-attributed diagnostic |
+| `issue-130-horizontal-facing-angle` | #130 catalog-backed `eventPlayer.getHorizontalFacingAngle()` member-value lowering |
 | `issue-131-spec-visibility` | #131 `SpecVisibility.NEVER` to canonical `VISIBLE_NEVER` enum mapping |
 | `issue-47-control-flow` | #47 pinned oracle-backed control-flow lowering probe: if/elif/else, while, range-for, do-while expansion, switch fallthrough/default, and direct break |
 | `issue-47-unsupported` | #47 negative probe: a break hidden inside a conditional switch arm is accepted by the source implementation/oracle but rejected by the compiler with a stable source-attributed diagnostic |
diff --git a/compatibility/fixtures/real-world/6v6-adjustments/fixture.json b/compatibility/fixtures/real-world/6v6-adjustments/fixture.json
index 64b8ec7..8e0ad1d 100644
--- a/compatibility/fixtures/real-world/6v6-adjustments/fixture.json
+++ b/compatibility/fixtures/real-world/6v6-adjustments/fixture.json
@@ -141,5 +141,15 @@
   },
   "runtimeSeconds": 9.7,
   "schemaVersion": 1,
-  "source": "main.opy"
+  "source": "main.opy",
+  "regressions": [
+    {
+      "id": "real-world/6v6-adjustments/get-horizontal-facing-angle",
+      "source": "regressions/get-horizontal-facing-angle.opy",
+      "derivedFrom": "heroes/juno/orbital_ray.opy",
+      "expectedReferenceStatus": "success",
+      "kind": "minimized-regression",
+      "provenance": "oracle:real-world/6v6-adjustments/oracle.json; source paths 20-24 in heroes/juno/orbital_ray.opy"
+    }
+  ]
 }
diff --git a/compatibility/fixtures/real-world/6v6-adjustments/regressions/get-horizontal-facing-angle.opy b/compatibility/fixtures/real-world/6v6-adjustments/regressions/get-horizontal-facing-angle.opy
new file mode 100644
index 0000000..f5475fa
--- /dev/null
+++ b/compatibility/fixtures/real-world/6v6-adjustments/regressions/get-horizontal-facing-angle.opy
@@ -0,0 +1,5 @@
+globalvar horizontalAngle
+
+rule "horizontal facing angle residual":
+    @Event eachPlayer
+    horizontalAngle = eventPlayer.getHorizontalFacingAngle()
diff --git a/compatibility/fixtures/real-world/overpy-client-to-server/fixture.json b/compatibility/fixtures/real-world/overpy-client-to-server/fixture.json
index 009d6df..005a366 100644
--- a/compatibility/fixtures/real-world/overpy-client-to-server/fixture.json
+++ b/compatibility/fixtures/real-world/overpy-client-to-server/fixture.json
@@ -42,6 +42,14 @@
       "expectedReferenceStatus": "success",
       "kind": "minimized-regression",
       "provenance": "oracle:real-world/overpy-client-to-server/oracle.json; source path 42"
+    },
+    {
+      "id": "real-world/overpy-client-to-server/get-horizontal-facing-angle",
+      "source": "regressions/get-horizontal-facing-angle.opy",
+      "derivedFrom": "clientToServer.opy",
+      "expectedReferenceStatus": "success",
+      "kind": "minimized-regression",
+      "provenance": "oracle:real-world/overpy-client-to-server/oracle.json; source paths 46, 58, 60, 62, 64"
     }
   ]
 }
diff --git a/compatibility/fixtures/real-world/overpy-client-to-server/regressions/get-horizontal-facing-angle.opy b/compatibility/fixtures/real-world/overpy-client-to-server/regressions/get-horizontal-facing-angle.opy
new file mode 100644
index 0000000..f5475fa
--- /dev/null
+++ b/compatibility/fixtures/real-world/overpy-client-to-server/regressions/get-horizontal-facing-angle.opy
@@ -0,0 +1,5 @@
+globalvar horizontalAngle
+
+rule "horizontal facing angle residual":
+    @Event eachPlayer
+    horizontalAngle = eventPlayer.getHorizontalFacingAngle()
diff --git a/compatibility/fixtures/synthetic/issue-130-horizontal-facing-angle/fixture.json b/compatibility/fixtures/synthetic/issue-130-horizontal-facing-angle/fixture.json
new file mode 100644
index 0000000..40d746a
--- /dev/null
+++ b/compatibility/fixtures/synthetic/issue-130-horizontal-facing-angle/fixture.json
@@ -0,0 +1,17 @@
+{
+  "schemaVersion": 1,
+  "id": "synthetic/issue-130-horizontal-facing-angle",
+  "category": "synthetic",
+  "features": [
+    "semantics/receiver-members",
+    "compilation/catalog-backed-member-values"
+  ],
+  "source": "source.opy",
+  "expectedStatus": "success",
+  "provenance": {
+    "kind": "minimized-regression",
+    "origin": "wrightkit/opy-rs#130 acceptance reproduction",
+    "license": "AGPL-3.0-or-later",
+    "redistributable": true
+  }
+}
diff --git a/compatibility/fixtures/synthetic/issue-130-horizontal-facing-angle/oracle.json b/compatibility/fixtures/synthetic/issue-130-horizontal-facing-angle/oracle.json
new file mode 100644
index 0000000..857282e
--- /dev/null
+++ b/compatibility/fixtures/synthetic/issue-130-horizontal-facing-angle/oracle.json
@@ -0,0 +1,33 @@
+{
+  "compile": {
+    "diagnostics": [],
+    "exitCode": 0,
+    "status": "success",
+    "stdout": "",
+    "workshop": "variables {\n    global:\n        0: horizontalAngle\n}\n\nrule (\"horizontal facing angle\") {\n    event {\n        Ongoing - Each Player;\n        All;\n        All;\n    }\n    actions {\n        Set Global Variable(horizontalAngle, Horizontal Facing Angle Of(Event Player));\n    }\n}\n",
+    "workshopExact": "variables {\n    global:\n        0: horizontalAngle\n}\n\nrule (\"horizontal facing angle\") {\n    event {\n        Ongoing - Each Player;\n        All;\n        All;\n    }\n    actions {\n        Set Global Variable(horizontalAngle, Horizontal Facing Angle Of(Event Player));\n    }\n}\n\n",
+    "workshopSha256": "cfa82e04854ba3836ac997c475a095afa044b8f5c1ca803fa32f3c1b909c35c9"
+  },
+  "fixture": "synthetic/issue-130-horizontal-facing-angle",
+  "input": {
+    "files": [
+      {
+        "path": "source.opy",
+        "sha256": "114a0e69c9c49618e3233a5b76eb32948edd0a1478a1d24303db5f910343c949"
+      }
+    ],
+    "sha256": "b70bd3106b5293de1ec9408833a8e1a8744579238ddd0f5400246826c3d5f2dd",
+    "source": "source.opy"
+  },
+  "oracle": {
+    "gitHead": "1e2688954302a402d076944b46db07efb14d7b61",
+    "integrity": "sha512-oX17nauJcPTaKIrRFY/rD0Rl8atqFUVv9Hg2TKH+A68/fC8+ZO344Mkd1A/Y0oOVp1hr5tktMBjzMEDDnMEYUw==",
+    "language": "en-US",
+    "license": "GPL-3.0-only",
+    "name": "overpy",
+    "registryTarball": "https://registry.npmjs.org/overpy/-/overpy-9.7.10.tgz",
+    "repository": "https://github.com/Zezombye/overpy",
+    "version": "9.7.10"
+  },
+  "schemaVersion": 1
+}
diff --git a/compatibility/fixtures/synthetic/issue-130-horizontal-facing-angle/source.opy b/compatibility/fixtures/synthetic/issue-130-horizontal-facing-angle/source.opy
new file mode 100644
index 0000000..3270395
--- /dev/null
+++ b/compatibility/fixtures/synthetic/issue-130-horizontal-facing-angle/source.opy
@@ -0,0 +1,5 @@
+globalvar horizontalAngle
+
+rule "horizontal facing angle":
+    @Event eachPlayer
+    horizontalAngle = eventPlayer.getHorizontalFacingAngle()
diff --git a/crates/opy-rs/src/compiler/integration_tests.rs b/crates/opy-rs/src/compiler/integration_tests.rs
index f7be810..9b46e93 100644
--- a/crates/opy-rs/src/compiler/integration_tests.rs
+++ b/crates/opy-rs/src/compiler/integration_tests.rs
@@ -14,6 +14,8 @@ mod issue_114_hud_subheader;
 mod issue_115_string_continuation;
 #[path = "tests/issue_129_included_main_file.rs"]
 mod issue_129_included_main_file;
+#[path = "tests/issue_130_horizontal_facing_angle.rs"]
+mod issue_130_horizontal_facing_angle;
 #[path = "tests/issue_131_spec_visibility.rs"]
 mod issue_131_spec_visibility;
 #[path = "tests/issue_42_oracle.rs"]
diff --git a/crates/opy-rs/src/compiler/tests/issue_130_horizontal_facing_angle.rs b/crates/opy-rs/src/compiler/tests/issue_130_horizontal_facing_angle.rs
new file mode 100644
index 0000000..e7f6e9f
--- /dev/null
+++ b/crates/opy-rs/src/compiler/tests/issue_130_horizontal_facing_angle.rs
@@ -0,0 +1,99 @@
+//! Canonical-WIR lowering evidence for issue #130.
+
+use std::path::{Path, PathBuf};
+
+use crate::Compiler;
+use workshop_rs::catalog::{Catalog, Locale};
+use workshop_rs::roundtrip::equivalent;
+use workshop_rs::wir::{Action, Value};
+
+fn fixture_dir() -> PathBuf {
+    Path::new(env!("CARGO_MANIFEST_DIR"))
+        .join("../../compatibility/fixtures/synthetic/issue-130-horizontal-facing-angle")
+}
+
+#[test]
+fn horizontal_facing_angle_member_matches_the_pinned_canonical_wir() {
+    let dir = fixture_dir();
+    let source = std::fs::read_to_string(dir.join("source.opy")).expect("source is readable");
+    let hir = crate::compile(&source, "source.opy", &dir).expect("source must resolve");
+    let artifact = Compiler::new()
+        .expect("compiler initializes")
+        .compile_hir(&hir)
+        .expect("getHorizontalFacingAngle lowers to canonical WIR");
+
+    let oracle: serde_json::Value = serde_json::from_str(
+        &std::fs::read_to_string(dir.join("oracle.json")).expect("oracle is readable"),
+    )
+    .expect("oracle is valid JSON");
+    let oracle_wir = workshop_rs::parser::parse(
+        oracle["compile"]["workshop"]
+            .as_str()
+            .expect("oracle workshop text is present"),
+        &Catalog::builtin().expect("catalog is available"),
+        &Locale::new("en-US"),
+    )
+    .expect("oracle workshop text parses");
+    assert!(equivalent(&artifact.wir, &oracle_wir));
+
+    let rule = artifact
+        .wir
+        .rules
+        .get(workshop_rs::wir::RuleId::from_index(0))
+        .expect("fixture has one rule");
+    let Action::SetGlobalVariable {
+        variable, value, ..
+    } = artifact
+        .wir
+        .actions
+        .get(rule.actions[0])
+        .expect("rule captures the member value")
+    else {
+        panic!("expected direct global assignment");
+    };
+    assert_eq!(
+        artifact
+            .wir
+            .global_variables
+            .get(*variable)
+            .expect("global variable")
+            .name,
+        "horizontalAngle"
+    );
+    let Value::Call { name, args } = &artifact
+        .wir
+        .values
+        .get(*value)
+        .expect("horizontal facing angle value")
+        .value
+    else {
+        panic!("expected catalog member value call");
+    };
+    assert_eq!(name, "getHorizontalFacingAngle");
+    assert_eq!(args.len(), 1);
+    assert!(matches!(
+        &artifact
+            .wir
+            .values
+            .get(args[0])
+            .expect("receiver value")
+            .value,
+        Value::EventPlayer
+    ));
+}
+
+#[test]
+fn horizontal_facing_angle_arity_failure_keeps_source_provenance() {
+    let source = "rule \"r\":\n    @Event eachPlayer\n    @Condition eventPlayer.getHorizontalFacingAngle(1) == 0\n";
+    let error = crate::compile(source, "source.opy", Path::new("."))
+        .expect_err("member arity must be rejected");
+    assert_eq!(error.code, "invalid-arity");
+    assert_eq!(
+        error
+            .span
+            .expect("diagnostic is source-attributed")
+            .start
+            .line,
+        3
+    );
+}
diff --git a/crates/opy-rs/src/manifest/data/manifest.json b/crates/opy-rs/src/manifest/data/manifest.json
index e220783..9e40bbc 100644
--- a/crates/opy-rs/src/manifest/data/manifest.json
+++ b/crates/opy-rs/src/manifest/data/manifest.json
@@ -641,6 +641,16 @@
       "params": [],
       "receiver": "Player"
     },
+    {
+      "catalogId": "getHorizontalFacingAngle",
+      "evidence": [
+        "get-horizontal-facing-angle"
+      ],
+      "id": "getHorizontalFacingAngle",
+      "kind": "memberValue",
+      "params": [],
+      "receiver": "Player"
+    },
     {
       "catalogId": "isDummy",
       "evidence": [
diff --git a/crates/opy-rs/src/manifest/probes/get-horizontal-facing-angle.opy b/crates/opy-rs/src/manifest/probes/get-horizontal-facing-angle.opy
new file mode 100644
index 0000000..e67cd70
--- /dev/null
+++ b/crates/opy-rs/src/manifest/probes/get-horizontal-facing-angle.opy
@@ -0,0 +1,5 @@
+globalvar horizontalAngle
+
+rule "r":
+    @Event eachPlayer
+    horizontalAngle = eventPlayer.getHorizontalFacingAngle()
diff --git a/crates/opy-rs/src/manifest/probes/probes.json b/crates/opy-rs/src/manifest/probes/probes.json
index b55bc14..8ec40e5 100644
--- a/crates/opy-rs/src/manifest/probes/probes.json
+++ b/crates/opy-rs/src/manifest/probes/probes.json
@@ -134,6 +134,13 @@
       "sha256": "f8cc098038f525941ebccac6fddaed85de3972804c76f97438606a3dee101901",
       "source": "generic-builtins.opy"
     },
+    {
+      "expect": "success",
+      "id": "get-horizontal-facing-angle",
+      "outputSha256": "e14857154460461eb274daa9853e02578cff3b85e445eccc218f1cf212c1f322",
+      "sha256": "0a333d935710b4de21ad1a2af0809cc519fdffd1be533539e7b8ffd0a0fefb2e",
+      "source": "get-horizontal-facing-angle.opy"
+    },
     {
       "diagnosticContains": "Unknown function 'setMoveSpeed'",
       "expect": "failure",
diff --git a/crates/opy-rs/tests/differential.rs b/crates/opy-rs/tests/differential.rs
index 1c64d22..6d765b5 100644
--- a/crates/opy-rs/tests/differential.rs
+++ b/crates/opy-rs/tests/differential.rs
@@ -253,6 +253,12 @@ fn declared_corpus() -> BTreeMap<&'static str, Case> {
         true,
         "Issue #114 shared hudSubheader action; canonical WIR lowering is constrained by the dedicated compiler test.",
     );
+    resolve(
+        &mut cases,
+        "synthetic/issue-130-horizontal-facing-angle",
+        true,
+        "Issue #130 catalog-backed eventPlayer.getHorizontalFacingAngle() member value; canonical WIR lowering is constrained by the dedicated compiler test.",
+    );
     resolve(
         &mut cases,
         "synthetic/issue-131-spec-visibility",
@@ -470,7 +476,7 @@ fn declared_corpus() -> BTreeMap<&'static str, Case> {
         &mut cases,
         "real-world/overpy-client-to-server",
         Some("parse-error"),
-        "the chained ternary and isDummy regressions resolve; the full project reaches the next unsupported member (`getHorizontalFacingAngle`). Gap: reference accepts, native rejects (documented).",
+        "the chained ternary, isDummy, and getHorizontalFacingAngle regressions resolve; the full project reaches the next unknown value (`horizontalAngleOfDirection`). Gap: reference accepts, native rejects (documented).",
     );
     diagnostic(
         &mut cases,