diff --git a/src/UniTask.NetCore/Linq/Reverse.cs b/src/UniTask.NetCore/Linq/Reverse.cs
index c59f44b..4a553ca 100644
--- a/src/UniTask.NetCore/Linq/Reverse.cs
+++ b/src/UniTask.NetCore/Linq/Reverse.cs
@@ -1,775 +1,76 @@
-namespace Cysharp.Threading.Tasks.Linq
+using Cysharp.Threading.Tasks.Internal;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading;
+
+namespace Cysharp.Threading.Tasks.Linq
 {
-    internal sealed class Reverse
+    public static partial class UniTaskAsyncEnumerable
     {
+        public static IUniTaskAsyncEnumerable<TSource> Reverse<TSource>(this IUniTaskAsyncEnumerable<TSource> source)
+        {
+            Error.ThrowArgumentNullException(source, nameof(source));
+            return new Reverse<TSource>(source);
+        }
     }
 
-
-}
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+    internal sealed class Reverse<TSource> : IUniTaskAsyncEnumerable<TSource>
+    {
+        readonly IUniTaskAsyncEnumerable<TSource> source;
+
+        public Reverse(IUniTaskAsyncEnumerable<TSource> source)
+        {
+            this.source = source;
+        }
+
+        public IUniTaskAsyncEnumerator<TSource> GetAsyncEnumerator(CancellationToken cancellationToken = default)
+        {
+            return new Enumerator(source, cancellationToken);
+        }
+
+        sealed class Enumerator : MoveNextSource, IUniTaskAsyncEnumerator<TSource>
+        {
+            readonly IUniTaskAsyncEnumerable<TSource> source;
+            CancellationToken cancellationToken;
+
+            TSource[] array;
+            int index;
+
+            public Enumerator(IUniTaskAsyncEnumerable<TSource> source, CancellationToken cancellationToken)
+            {
+                this.source = source;
+                this.cancellationToken = cancellationToken;
+            }
+
+            public TSource Current { get; private set; }
+
+            // after consumed array, don't use await so allow async(not require UniTaskCompletionSourceCore).
+            public async UniTask<bool> MoveNextAsync()
+            {
+                cancellationToken.ThrowIfCancellationRequested();
+
+                if (array == null)
+                {
+                    array = await source.ToArrayAsync(cancellationToken);
+                    index = array.Length - 1;
+                }
+
+                if (index != -1)
+                {
+                    Current = array[index];
+                    --index;
+                    return true;
+                }
+                else
+                {
+                    return false;
+                }
+            }
+
+            public UniTask DisposeAsync()
+            {
+                return default;
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/UniTask.NetCoreSandbox/Program.cs b/src/UniTask.NetCoreSandbox/Program.cs
index ae8d8c7..843564a 100644
--- a/src/UniTask.NetCoreSandbox/Program.cs
+++ b/src/UniTask.NetCoreSandbox/Program.cs
@@ -39,17 +39,8 @@ namespace NetCoreSandbox
 
         static async Task Main(string[] args)
         {
-            Console.WriteLine("YEAH");
-            try
-            {
-                var xs = await UniTaskAsyncEnumerable.Range(1, 10).Concat(UniTaskAsyncEnumerable.Throw<int>(new InvalidOperationException("something")))
-                    .SumAsync();
-            }
-            catch (Exception ex)
-            {
-                Console.WriteLine("EX");
-                Console.WriteLine(ex);
-            }
+            var foo = Enumerable.Range(1, 10).ToArray().AsEnumerable().GetEnumerator() as IEnumerator<int>;
+            Console.WriteLine(foo.GetType().FullName);
         }
 
 
diff --git a/src/UniTask.NetCoreTests/Linq/Projection.cs b/src/UniTask.NetCoreTests/Linq/Projection.cs
new file mode 100644
index 0000000..49f3017
--- /dev/null
+++ b/src/UniTask.NetCoreTests/Linq/Projection.cs
@@ -0,0 +1,40 @@
+using Cysharp.Threading.Tasks;
+using Cysharp.Threading.Tasks.Linq;
+using FluentAssertions;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reactive.Concurrency;
+using System.Reactive.Linq;
+using System.Threading.Tasks;
+using Xunit;
+
+
+namespace NetCoreTests.Linq
+{
+    public class Projection
+    {
+        [Theory]
+        [InlineData(0, 0)]
+        [InlineData(0, 1)]
+        [InlineData(0, 2)]
+        [InlineData(0, 10)]
+        public async Task Reverse(int start, int count)
+        {
+            var xs = await Enumerable.Range(start, count).ToUniTaskAsyncEnumerable().Reverse().ToArrayAsync();
+            var ys = Enumerable.Range(start, count).Reverse().ToArray();
+
+            xs.Should().BeEquivalentTo(ys);
+        }
+
+        [Fact]
+        public async Task ReverseException()
+        {
+            foreach (var item in UniTaskTestException.Throws())
+            {
+                var xs = item.Reverse().ToArrayAsync();
+                await Assert.ThrowsAsync<UniTaskTestException>(async () => await xs);
+            }
+        }
+    }
+}