diff --git a/crates/wasm-actor/tests/wasm_actor.rs b/crates/wasm-actor/tests/wasm_actor.rs
index cba9a32..5e61af3 100644
--- a/crates/wasm-actor/tests/wasm_actor.rs
+++ b/crates/wasm-actor/tests/wasm_actor.rs
@@ -11002,4 +11002,137 @@ fn echo_after_hundred_idle_ticks() {
     rt.send_to(addr, framed_msg(inbox.addr(), b"after")).unwrap();
     rt.tick();
     assert_eq!(inbox.try_recv().unwrap().0, b"after");
+}
+
+// ── Cycle 76 ─────────────────────────────────────────────────────────────────
+
+// Guest with complex send pattern: send to two different addresses in one handle
+#[test]
+fn guest_sends_to_two_addresses_in_one_handle() {
+    let wat = r#"(module
+        (import "swactor" "send" (func $send (param i32 i32 i32)))
+        (memory (export "memory") 1)
+        (func (export "alloc") (param $len i32) (result i32) i32.const 1024)
+        (func (export "handle") (param $ptr i32) (param $len i32)
+            ;; Message layout: [addr1:32][addr2:32][payload:rest]
+            ;; Send payload to both addresses
+            (if (i32.ge_u (local.get $len) (i32.const 65))
+                (then
+                    ;; Send to addr1
+                    (call $send
+                        (local.get $ptr)
+                        (i32.add (local.get $ptr) (i32.const 64))
+                        (i32.sub (local.get $len) (i32.const 64))
+                    )
+                    ;; Send to addr2
+                    (call $send
+                        (i32.add (local.get $ptr) (i32.const 32))
+                        (i32.add (local.get $ptr) (i32.const 64))
+                        (i32.sub (local.get $len) (i32.const 64))
+                    )
+                )
+            )
+        )
+    )"#;
+    let engine = SharedEngine::new().unwrap();
+    let actor = WasmActorBuilder::new(engine, wat::parse_str(wat).unwrap())
+        .build().unwrap();
+    let rt = Runtime::new(RuntimeConfig::default());
+    let inbox1 = rt.new_inbox::<ByteMessage>().unwrap();
+    let inbox2 = rt.new_inbox::<ByteMessage>().unwrap();
+    let addr = rt.spawn(actor).unwrap();
+
+    let mut msg = Vec::new();
+    msg.extend_from_slice(&inbox1.addr().0);  // addr1
+    msg.extend_from_slice(&inbox2.addr().0);  // addr2
+    msg.extend_from_slice(b"shared-data");      // payload
+    rt.send_to(addr, ByteMessage(msg)).unwrap();
+    rt.tick();
+
+    let r1 = inbox1.try_recv().expect("inbox1 should receive");
+    let r2 = inbox2.try_recv().expect("inbox2 should receive");
+    assert_eq!(r1.0, b"shared-data");
+    assert_eq!(r2.0, b"shared-data");
+}
+
+// Build actor, clone engine, build another actor — verify independence
+#[test]
+fn engine_clone_builds_independent_actors() {
+    let engine = SharedEngine::new().unwrap();
+    let clone = engine.clone();
+    let a1 = WasmActorBuilder::new(engine, guest_wasm("echo")).build().unwrap();
+    let a2 = WasmActorBuilder::new(clone, guest_wasm("double")).build().unwrap();
+
+    let rt = Runtime::new(RuntimeConfig::default());
+    let inbox = rt.new_inbox::<ByteMessage>().unwrap();
+    let addr1 = rt.spawn(a1).unwrap();
+    let addr2 = rt.spawn(a2).unwrap();
+
+    rt.send_to(addr1, framed_msg(inbox.addr(), b"A")).unwrap();
+    rt.send_to(addr2, framed_msg(inbox.addr(), b"B")).unwrap();
+    rt.tick();
+
+    let msgs: Vec<Vec<u8>> = std::iter::from_fn(|| inbox.try_recv().map(|m| m.0)).collect();
+    assert_eq!(msgs.len(), 3, "1 echo + 2 double = 3");
+}
+
+// Guest handles 500 messages in a single tick
+#[test]
+fn five_hundred_messages_in_one_tick() {
+    let engine = SharedEngine::new().unwrap();
+    let actor = WasmActorBuilder::new(engine, guest_wasm("echo")).build().unwrap();
+    let rt = Runtime::new(RuntimeConfig::default());
+    let inbox = rt.new_inbox::<ByteMessage>().unwrap();
+    let addr = rt.spawn(actor).unwrap();
+
+    for i in 0..500u16 {
+        let payload = i.to_le_bytes().to_vec();
+        rt.send_to(addr, framed_msg(inbox.addr(), &payload)).unwrap();
+    }
+    // May need multiple ticks depending on budget
+    for _ in 0..20 {
+        rt.tick();
+    }
+
+    let msgs: Vec<_> = std::iter::from_fn(|| inbox.try_recv()).collect();
+    assert_eq!(msgs.len(), 500, "all 500 messages echoed");
+}
+
+// Guest with return in the middle of handle — early exit
+#[test]
+fn guest_early_return_from_handle() {
+    let wat = r#"(module
+        (import "swactor" "send" (func $send (param i32 i32 i32)))
+        (memory (export "memory") 1)
+        (func (export "alloc") (param $len i32) (result i32) i32.const 1024)
+        (func (export "handle") (param $ptr i32) (param $len i32)
+            ;; If len < 33, return early (no send)
+            (if (i32.lt_u (local.get $len) (i32.const 33))
+                (then return)
+            )
+            ;; Only reaches here for long messages
+            (call $send
+                (local.get $ptr)
+                (i32.add (local.get $ptr) (i32.const 32))
+                (i32.sub (local.get $len) (i32.const 32))
+            )
+        )
+    )"#;
+    let engine = SharedEngine::new().unwrap();
+    let actor = WasmActorBuilder::new(engine, wat::parse_str(wat).unwrap())
+        .build().unwrap();
+    let rt = Runtime::new(RuntimeConfig::default());
+    let inbox = rt.new_inbox::<ByteMessage>().unwrap();
+    let addr = rt.spawn(actor).unwrap();
+
+    // Short message — no response
+    rt.send_to(addr, ByteMessage(vec![0u8; 10])).unwrap();
+    rt.tick();
+    assert!(inbox.try_recv().is_none());
+
+    // Long message — response
+    rt.send_to(addr, framed_msg(inbox.addr(), b"long-enough")).unwrap();
+    rt.tick();
+    let resp = inbox.try_recv().expect("long message should echo");
+    assert_eq!(resp.0, b"long-enough");
 }
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