test(engine): cover Overencumbered token ownership

crates/engine/src/parser/oracle_effect/subject.rs

@@ -2533,7 +2533,7 @@ pub(super) fn parse_subject_application(
             is_optional: false,
         });
     }
-    // CR 303.4b + CR 702.5a + CR 701.17a (issues #5947, #5271): "enchanted
+    // CR 303.4b + CR 303.4m + CR 702.5a (issues #5947, #5271): "enchanted
     // player" / "enchanted opponent" name the Aura's attached player host —
     // `AttachedTo`, not a Typed EnchantedBy filter (which is object-only).
     // The opponent qualifier constrains attachment when the Aura enters; its

crates/engine/tests/integration/issue_5271_overencumbered_tokens.rs

@@ -0,0 +1,51 @@
+use engine::game::game_object::AttachTarget;
+use engine::game::scenario::{GameScenario, P0, P1};
+use engine::types::mana::ManaCost;
+use engine::types::phase::Phase;
+
+const OVERENCUMBERED_ORACLE: &str = "Enchant opponent\n\
+When this Aura enters, enchanted opponent creates a Clue token, a Food token, and a Junk token.\n\
+At the beginning of combat on enchanted opponent's turn, that player may pay {1} for each artifact they control. If they don't, creatures can't attack this combat.";
+
+/// CR 111.2 + CR 303.4b + CR 608.2c: a player Aura's ETB resolves its
+/// shared-verb token list for the enchanted opponent, not the Aura's controller.
+#[test]
+fn issue_5271_overencumbered_etb_gives_every_token_to_enchanted_opponent() {
+    let mut scenario = GameScenario::new();
+    scenario.at_phase(Phase::PreCombatMain);
+    let aura = {
+        let mut builder = scenario.add_creature_to_hand(P0, "Overencumbered", 0, 0);
+        builder
+            .as_enchantment()
+            .with_subtypes(vec!["Aura", "Curse"])
+            .with_mana_cost(ManaCost::zero())
+            .from_oracle_text_with_keywords(&["Enchant opponent"], OVERENCUMBERED_ORACLE);
+        builder.id()
+    };
+
+    let mut runner = scenario.build();
+    runner.cast(aura).target_player(P1).resolve();
+    assert_eq!(
+        runner.state().objects.get(&aura).unwrap().attached_to,
+        Some(AttachTarget::Player(P1)),
+        "the resolving Aura must attach to its chosen opponent before its ETB resolves"
+    );
+    runner.advance_until_stack_empty();
+
+    for token_name in ["Clue", "Food", "Junk"] {
+        let token = runner
+            .state()
+            .objects
+            .values()
+            .find(|object| object.name == token_name && object.is_token)
+            .unwrap_or_else(|| panic!("Overencumbered must create a {token_name} token"));
+        assert_eq!(
+            token.owner, P1,
+            "{token_name} must be owned by the enchanted opponent"
+        );
+        assert_eq!(
+            token.controller, P1,
+            "{token_name} must be controlled by the enchanted opponent"
+        );
+    }
+}

crates/engine/tests/integration/main.rs

@@ -599,6 +599,7 @@ mod issue_5247_kinetic_ooze_conditional_multi_target;
 mod issue_5252_additional_sacrifice_after_mana_abilities;
 mod issue_5254_declaration_in_stone_clue_owner;
 mod issue_5268_invincible_iron_man;
+mod issue_5271_overencumbered_tokens;
 mod issue_5274_call_the_spirit_dragons;
 mod issue_5279_grave_sifter;
 mod issue_5282_nissa_ultimate_emblem_search;