diff --git a/src/index.ts b/src/index.ts
index f3490973..a57fb2f7 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -24,10 +24,29 @@ export * from './core/types/magic-regexp'
 // Add additional overload to global String object types to allow for typed capturing groups
 declare global {
   interface String {
-    match<R extends MagicRegExp<string, string, string>>(regexp: R): MagicRegExpMatchArray<R> | null
+    match<R extends MagicRegExp<string, string, Exclude<Flag, 'g'>>>(
+      regexp: R
+    ): MagicRegExpMatchArray<R> | null
+    match<R extends MagicRegExp<string, string, 'g'>>(regexp: R): string[] | null
+
+    /** @deprecated String.matchAll requires global flag to be set. */
+    matchAll<R extends MagicRegExp<string, string, never>>(regexp: R): never
+    /** @deprecated String.matchAll requires global flag to be set. */
+    matchAll<R extends MagicRegExp<string, string, Exclude<Flag, 'g'>>>(regexp: R): never
 
     matchAll<R extends MagicRegExp<string, string, string>>(
       regexp: R
     ): IterableIterator<MagicRegExpMatchArray<R>>
+
+    /** @deprecated String.replaceAll requires global flag to be set. */
+    replaceAll<R extends MagicRegExp<string, string, never>>(
+      searchValue: R,
+      replaceValue: string | ((substring: string, ...args: any[]) => string)
+    ): never
+    /** @deprecated String.replaceAll requires global flag to be set. */
+    replaceAll<R extends MagicRegExp<string, string, Exclude<Flag, 'g'>>>(
+      searchValue: R,
+      replaceValue: string | ((substring: string, ...args: any[]) => string)
+    ): never
   }
 }
diff --git a/test/augments.test.ts b/test/augments.test.ts
index 3b0bb47b..1ca5e92b 100644
--- a/test/augments.test.ts
+++ b/test/augments.test.ts
@@ -15,21 +15,30 @@ describe('String', () => {
   it('.match global', () => {
     const result = 'test'.match(createRegExp(char.as('foo'), [global]))
     expect(Array.isArray(result)).toBeTruthy()
+    // @ts-expect-error
     expect(result?.groups).toBeUndefined()
-    // TODO: https://github.com/danielroe/magic-regexp/issues/26
-    // expectTypeOf(result).toEqualTypeOf<null | string[]>()
+    expectTypeOf(result).toEqualTypeOf<null | string[]>()
   })
   it.todo('.matchAll non-global', () => {
-    // TODO: @ts-expect-error
-    'test'.matchAll(createRegExp(char.as('foo')))
+    // should be deprecated
+    expectTypeOf('test'.matchAll(createRegExp(char.as('foo')))).toEqualTypeOf<never>()
+    expectTypeOf('test'.matchAll(createRegExp(char.as('foo'), ['m']))).toEqualTypeOf<never>()
   })
   it('.matchAll global', () => {
     const results = 'test'.matchAll(createRegExp(char.as('foo'), [global]))
-    expect(Array.isArray([...results])).toBeTruthy()
+    let count = 0
     for (const result of results) {
-      expect(result?.groups).toBeUndefined()
-      // TODO: https://github.com/danielroe/magic-regexp/issues/26
-      // expectTypeOf(result).toEqualTypeOf<null | string[]>()
+      count++
+      expect([...'test'].includes(result?.groups.foo || '')).toBeTruthy()
+      expectTypeOf(result).toEqualTypeOf<
+        MagicRegExpMatchArray<MagicRegExp<'/(?<foo>.)/g', 'foo', 'g'>>
+      >()
     }
+    expect(count).toBe(4)
+  })
+  it.todo('.replaceAll non-global', () => {
+    // should be deprecated
+    expectTypeOf('test'.replaceAll(createRegExp(char.as('foo')), '')).toEqualTypeOf<never>()
+    expectTypeOf('test'.replaceAll(createRegExp(char.as('foo'), ['m']), '')).toEqualTypeOf<never>()
   })
 })