diff --git a/packages/api/src/query.types.ts b/packages/api/src/query.types.ts
index d129c01f7c..a2c8874c68 100644
--- a/packages/api/src/query.types.ts
+++ b/packages/api/src/query.types.ts
@@ -3,7 +3,7 @@
 
 import { Observable } from 'rxjs';
 import { Option, Raw, Vec } from '@polkadot/types/codec';
-import { Bytes, Null, bool, u32, u64 } from '@polkadot/types';
+import { Bytes, bool, u32, u64 } from '@polkadot/types';
 import { AccountId, AccountIndex, Balance, BalanceOf, BlockNumber, Hash, Index, KeyTypeId, Moment, Perbill, ValidatorId, Weight } from '@polkadot/types/interfaces/runtime';
 import { UncleEntryItem } from '@polkadot/types/interfaces/authorship';
 import { BabeAuthorityWeight, MaybeVrf } from '@polkadot/types/interfaces/babe';
@@ -39,7 +39,7 @@ declare module './types' {
       digest: StorageEntryExact<ApiType, () => Observable<DigestOf>> & QueryableStorageEntry<ApiType>;
       events: StorageEntryExact<ApiType, () => Observable<Vec<EventRecord>>> & QueryableStorageEntry<ApiType>;
       eventCount: StorageEntryExact<ApiType, () => Observable<EventIndex>> & QueryableStorageEntry<ApiType>;
-      eventTopics: StorageEntryExact<ApiType, (key1: Null, key2: Hash | Uint8Array | string) => Observable<Vec<ITuple<[BlockNumber, EventIndex]>>>> & QueryableStorageEntry<ApiType>;
+      eventTopics: StorageEntryExact<ApiType, (key1: ITuple<[]>, key2: Hash | Uint8Array | string) => Observable<Vec<ITuple<[BlockNumber, EventIndex]>>>> & QueryableStorageEntry<ApiType>;
     };
     babe: {
       [index: string]: QueryableStorageEntry<ApiType>;
diff --git a/packages/metadata/src/Metadata/v0/static-substrate.json b/packages/metadata/src/Metadata/v0/static-substrate.json
index d7300adc95..0607480991 100644
--- a/packages/metadata/src/Metadata/v0/static-substrate.json
+++ b/packages/metadata/src/Metadata/v0/static-substrate.json
@@ -1495,7 +1495,7 @@
             "name": "ForcingNewEra",
             "modifier": "optional",
             "type": {
-              "Plain": "Null"
+              "Plain": "()"
             },
             "fallback": "0x00",
             "documentation": [
diff --git a/packages/metadata/src/Metadata/v1/static-substrate.json b/packages/metadata/src/Metadata/v1/static-substrate.json
index c8d7710113..4b95c3293b 100644
--- a/packages/metadata/src/Metadata/v1/static-substrate.json
+++ b/packages/metadata/src/Metadata/v1/static-substrate.json
@@ -977,7 +977,7 @@
               "name": "ForcingNewEra",
               "modifier": "optional",
               "type": {
-                "Plain": "Null"
+                "Plain": "()"
               },
               "fallback": "0x00",
               "documentation": [
diff --git a/packages/metadata/src/Metadata/v10/static-substrate.json b/packages/metadata/src/Metadata/v10/static-substrate.json
index 0946b3fb89..b827c25d0e 100644
--- a/packages/metadata/src/Metadata/v10/static-substrate.json
+++ b/packages/metadata/src/Metadata/v10/static-substrate.json
@@ -161,7 +161,7 @@
                 "type": {
                   "DoubleMap": {
                     "hasher": "blake2256",
-                    "key1": "Null",
+                    "key1": "()",
                     "key2": "Hash",
                     "value": "Vec<(BlockNumber,EventIndex)>",
                     "key2Hasher": "blake2256"
diff --git a/packages/metadata/src/Metadata/v11/static-substrate.json b/packages/metadata/src/Metadata/v11/static-substrate.json
index d843b66466..fca3e34c28 100644
--- a/packages/metadata/src/Metadata/v11/static-substrate.json
+++ b/packages/metadata/src/Metadata/v11/static-substrate.json
@@ -161,7 +161,7 @@
                 "type": {
                   "DoubleMap": {
                     "hasher": "blake2256",
-                    "key1": "Null",
+                    "key1": "()",
                     "key2": "Hash",
                     "value": "Vec<(BlockNumber,EventIndex)>",
                     "key2Hasher": "blake2256"
@@ -330,7 +330,7 @@
             {
               "name": "BatchExecuted",
               "args": [
-                "Vec<Result<Null,DispatchError>>"
+                "Vec<Result<(),DispatchError>>"
               ],
               "documentation": []
             }
diff --git a/packages/metadata/src/Metadata/v2/static-substrate.json b/packages/metadata/src/Metadata/v2/static-substrate.json
index 4bed254770..6ff9cddf7f 100644
--- a/packages/metadata/src/Metadata/v2/static-substrate.json
+++ b/packages/metadata/src/Metadata/v2/static-substrate.json
@@ -1004,7 +1004,7 @@
               "name": "ForcingNewEra",
               "modifier": "optional",
               "type": {
-                "Plain": "Null"
+                "Plain": "()"
               },
               "fallback": "0x00",
               "documentation": [
diff --git a/packages/metadata/src/Metadata/v3/static-substrate.json b/packages/metadata/src/Metadata/v3/static-substrate.json
index fcb6cda6b2..7426685eca 100644
--- a/packages/metadata/src/Metadata/v3/static-substrate.json
+++ b/packages/metadata/src/Metadata/v3/static-substrate.json
@@ -1063,7 +1063,7 @@
               "name": "ForcingNewEra",
               "modifier": "optional",
               "type": {
-                "Plain": "Null"
+                "Plain": "()"
               },
               "fallback": "0x00",
               "documentation": [
diff --git a/packages/metadata/src/Metadata/v4/static-substrate.json b/packages/metadata/src/Metadata/v4/static-substrate.json
index c40f6d22d7..e96c4bc7f0 100644
--- a/packages/metadata/src/Metadata/v4/static-substrate.json
+++ b/packages/metadata/src/Metadata/v4/static-substrate.json
@@ -161,7 +161,7 @@
               "type": {
                 "DoubleMap": {
                   "hasher": "blake2256",
-                  "key1": "Null",
+                  "key1": "()",
                   "key2": "Hash",
                   "value": "Vec<(BlockNumber,EventIndex)>",
                   "key2Hasher": "blake2_256"
@@ -1121,7 +1121,7 @@
               "name": "ForcingNewEra",
               "modifier": "optional",
               "type": {
-                "Plain": "Null"
+                "Plain": "()"
               },
               "fallback": "0x00",
               "documentation": [
diff --git a/packages/metadata/src/Metadata/v5/static-polkadot.json b/packages/metadata/src/Metadata/v5/static-polkadot.json
index 8773199b0c..02ebbb2323 100644
--- a/packages/metadata/src/Metadata/v5/static-polkadot.json
+++ b/packages/metadata/src/Metadata/v5/static-polkadot.json
@@ -161,7 +161,7 @@
               "type": {
                 "DoubleMap": {
                   "hasher": "blake2256",
-                  "key1": "Null",
+                  "key1": "()",
                   "key2": "Hash",
                   "value": "Vec<(BlockNumber,EventIndex)>",
                   "key2Hasher": "blake2256"
diff --git a/packages/metadata/src/Metadata/v5/static-substrate.json b/packages/metadata/src/Metadata/v5/static-substrate.json
index 87fb2a8dfe..28a357b76e 100644
--- a/packages/metadata/src/Metadata/v5/static-substrate.json
+++ b/packages/metadata/src/Metadata/v5/static-substrate.json
@@ -161,7 +161,7 @@
               "type": {
                 "DoubleMap": {
                   "hasher": "blake2256",
-                  "key1": "Null",
+                  "key1": "()",
                   "key2": "Hash",
                   "value": "Vec<(BlockNumber,EventIndex)>",
                   "key2Hasher": "blake2256"
diff --git a/packages/metadata/src/Metadata/v6/static-polkadot.json b/packages/metadata/src/Metadata/v6/static-polkadot.json
index 6288ce3249..aae6932753 100644
--- a/packages/metadata/src/Metadata/v6/static-polkadot.json
+++ b/packages/metadata/src/Metadata/v6/static-polkadot.json
@@ -161,7 +161,7 @@
               "type": {
                 "DoubleMap": {
                   "hasher": "blake2256",
-                  "key1": "Null",
+                  "key1": "()",
                   "key2": "Hash",
                   "value": "Vec<(BlockNumber,EventIndex)>",
                   "key2Hasher": "blake2256"
diff --git a/packages/metadata/src/Metadata/v6/static-substrate.json b/packages/metadata/src/Metadata/v6/static-substrate.json
index 30c6a0420e..1b86d7b826 100644
--- a/packages/metadata/src/Metadata/v6/static-substrate.json
+++ b/packages/metadata/src/Metadata/v6/static-substrate.json
@@ -184,7 +184,7 @@
               "type": {
                 "DoubleMap": {
                   "hasher": "blake2256",
-                  "key1": "Null",
+                  "key1": "()",
                   "key2": "Hash",
                   "value": "Vec<(BlockNumber,EventIndex)>",
                   "key2Hasher": "blake2256"
diff --git a/packages/metadata/src/Metadata/v7/static-polkadot.json b/packages/metadata/src/Metadata/v7/static-polkadot.json
index 14aebf8a27..b8d17ff281 100644
--- a/packages/metadata/src/Metadata/v7/static-polkadot.json
+++ b/packages/metadata/src/Metadata/v7/static-polkadot.json
@@ -185,7 +185,7 @@
                 "type": {
                   "DoubleMap": {
                     "hasher": "blake2256",
-                    "key1": "Null",
+                    "key1": "()",
                     "key2": "Hash",
                     "value": "Vec<(BlockNumber,EventIndex)>",
                     "key2Hasher": "blake2256"
diff --git a/packages/metadata/src/Metadata/v7/static-substrate.json b/packages/metadata/src/Metadata/v7/static-substrate.json
index 80cc6480c3..a8aae68523 100644
--- a/packages/metadata/src/Metadata/v7/static-substrate.json
+++ b/packages/metadata/src/Metadata/v7/static-substrate.json
@@ -185,7 +185,7 @@
                 "type": {
                   "DoubleMap": {
                     "hasher": "blake2256",
-                    "key1": "Null",
+                    "key1": "()",
                     "key2": "Hash",
                     "value": "Vec<(BlockNumber,EventIndex)>",
                     "key2Hasher": "blake2256"
@@ -332,7 +332,7 @@
             {
               "name": "BatchExecuted",
               "args": [
-                "Vec<Result<Null,DispatchError>>"
+                "Vec<Result<(),DispatchError>>"
               ],
               "documentation": []
             }
diff --git a/packages/metadata/src/Metadata/v8/static-substrate.json b/packages/metadata/src/Metadata/v8/static-substrate.json
index eb420652a9..6316ce9202 100644
--- a/packages/metadata/src/Metadata/v8/static-substrate.json
+++ b/packages/metadata/src/Metadata/v8/static-substrate.json
@@ -161,7 +161,7 @@
                 "type": {
                   "DoubleMap": {
                     "hasher": "blake2256",
-                    "key1": "Null",
+                    "key1": "()",
                     "key2": "Hash",
                     "value": "Vec<(BlockNumber,EventIndex)>",
                     "key2Hasher": "blake2256"
@@ -330,7 +330,7 @@
             {
               "name": "BatchExecuted",
               "args": [
-                "Vec<Result<Null,DispatchError>>"
+                "Vec<Result<(),DispatchError>>"
               ],
               "documentation": []
             }
diff --git a/packages/metadata/src/Metadata/v9/static-substrate.json b/packages/metadata/src/Metadata/v9/static-substrate.json
index 107b1fa48b..aba55d5296 100644
--- a/packages/metadata/src/Metadata/v9/static-substrate.json
+++ b/packages/metadata/src/Metadata/v9/static-substrate.json
@@ -161,7 +161,7 @@
                 "type": {
                   "DoubleMap": {
                     "hasher": "blake2256",
-                    "key1": "Null",
+                    "key1": "()",
                     "key2": "Hash",
                     "value": "Vec<(BlockNumber,EventIndex)>",
                     "key2Hasher": "blake2256"
@@ -325,7 +325,7 @@
             {
               "name": "BatchExecuted",
               "args": [
-                "Vec<Result<Null,DispatchError>>"
+                "Vec<Result<(),DispatchError>>"
               ],
               "documentation": []
             }
diff --git a/packages/types/src/codec/Result.spec.ts b/packages/types/src/codec/Result.spec.ts
index e783f85a38..ba679f711e 100644
--- a/packages/types/src/codec/Result.spec.ts
+++ b/packages/types/src/codec/Result.spec.ts
@@ -45,6 +45,6 @@ describe('Result', (): void => {
   });
 
   it('returns a proper raw typedef rom a built-in', (): void => {
-    expect(createType(registry, 'DispatchResult').toRawType()).toEqual('Result<Null,{"_enum":{"Other":"Null","CannotLookup":"Null","BadOrigin":"Null","Module":"{\\"index\\":\\"u8\\",\\"error\\":\\"u8\\"}"}}>');
+    expect(createType(registry, 'DispatchResult').toRawType()).toEqual('Result<(),{"_enum":{"Other":"Null","CannotLookup":"Null","BadOrigin":"Null","Module":"{\\"index\\":\\"u8\\",\\"error\\":\\"u8\\"}"}}>');
   });
 });
diff --git a/packages/types/src/codec/create/getTypeDef.spec.ts b/packages/types/src/codec/create/getTypeDef.spec.ts
index c921c1646e..74b8a8f727 100644
--- a/packages/types/src/codec/create/getTypeDef.spec.ts
+++ b/packages/types/src/codec/create/getTypeDef.spec.ts
@@ -19,12 +19,13 @@ describe('getTypeDef', (): void => {
     ).toThrow(/Unable to find closing matching/);
   });
 
-  it('maps empty tuples to Null', (): void => {
+  it('maps empty tuples to empty tuple', (): void => {
     expect(
       getTypeDef('()')
     ).toEqual({
-      info: TypeDefInfo.Plain,
-      type: 'Null'
+      info: TypeDefInfo.Tuple,
+      sub: [],
+      type: '()'
     });
   });
 
diff --git a/packages/types/src/codec/create/getTypeDef.ts b/packages/types/src/codec/create/getTypeDef.ts
index 5f25a97218..a4ad2ff08a 100644
--- a/packages/types/src/codec/create/getTypeDef.ts
+++ b/packages/types/src/codec/create/getTypeDef.ts
@@ -80,10 +80,12 @@ function _decodeFixedVec (value: TypeDef, type: string, _: string): TypeDef {
 
 // decode a tuple
 function _decodeTuple (value: TypeDef, _: string, subType: string): TypeDef {
-  value.sub = typeSplit(subType).map((inner): TypeDef =>
-    // eslint-disable-next-line @typescript-eslint/no-use-before-define
-    getTypeDef(inner)
-  );
+  value.sub = subType.length === 0
+    ? []
+    : typeSplit(subType).map((inner): TypeDef =>
+      // eslint-disable-next-line @typescript-eslint/no-use-before-define
+      getTypeDef(inner)
+    );
 
   return value;
 }
@@ -128,7 +130,6 @@ export function getTypeDef (_type: string, { name, displayName }: TypeDefOptions
   // create the type via Type, allowing types to be sanitized
   const type = sanitize(_type);
   const value: TypeDef = { info: TypeDefInfo.Plain, displayName, name, type };
-
   const nested = nestedExtraction.find((nested): boolean =>
     hasWrapper(type, nested)
   );
diff --git a/packages/types/src/codec/create/sanitize.ts b/packages/types/src/codec/create/sanitize.ts
index 8c5986c0f5..382bff43fa 100644
--- a/packages/types/src/codec/create/sanitize.ts
+++ b/packages/types/src/codec/create/sanitize.ts
@@ -24,8 +24,6 @@ const mappings: Mapper[] = [
   _removeGenerics(),
   // alias String -> Text (compat with jsonrpc methods)
   _alias('String', 'Text'),
-  // alias () -> Null
-  _alias('\\(\\)', 'Null'),
   // alias Vec<u8> -> Bytes
   _alias('Vec<u8>', 'Bytes'),
   // alias &[u8] -> Bytes
@@ -100,7 +98,7 @@ function _cleanupCompact (): Mapper {
 
 function _flattenSingleTuple (): Mapper {
   return (value: string): string => {
-    return value.replace(/\(([^,]*)\)/, '$1');
+    return value.replace(/\(([^,]+)\)/, '$1');
   };
 }
 
diff --git a/packages/types/src/interfaces/deprecated/definitions.ts b/packages/types/src/interfaces/deprecated/definitions.ts
index 719ed553e0..7b3ee14dc8 100644
--- a/packages/types/src/interfaces/deprecated/definitions.ts
+++ b/packages/types/src/interfaces/deprecated/definitions.ts
@@ -25,7 +25,7 @@ export default {
 
     // Metadata v4
     // :: consensus
-    InherentOfflineReport: 'Null', // this is '()' originally (we don't handle that)
+    InherentOfflineReport: '()',
     SessionKey: 'AccountId',
 
     // Metadata v5
diff --git a/packages/types/src/interfaces/deprecated/types.ts b/packages/types/src/interfaces/deprecated/types.ts
index e87af20af7..d1301b88a2 100644
--- a/packages/types/src/interfaces/deprecated/types.ts
+++ b/packages/types/src/interfaces/deprecated/types.ts
@@ -1,8 +1,9 @@
 // Auto-generated via `yarn build:interfaces`, do not edit
 /* eslint-disable @typescript-eslint/no-empty-interface */
 
+import { ITuple } from '@polkadot/types/types';
 import { Enum, Struct } from '@polkadot/types/codec';
-import { Bytes, Null, i8, u32, u64 } from '@polkadot/types/primitive';
+import { Bytes, i8, u32, u64 } from '@polkadot/types/primitive';
 import { AccountId, Balance } from '@polkadot/types/interfaces/runtime';
 
 /** Struct */
@@ -19,8 +20,8 @@ export interface Amount extends Balance {}
 /** u32 */
 export interface AssetOf extends u32 {}
 
-/** Null */
-export interface InherentOfflineReport extends Null {}
+/** ITuple<[]> */
+export interface InherentOfflineReport extends ITuple<[]> {}
 
 /** i8 */
 export interface LockPeriods extends i8 {}
diff --git a/packages/types/src/interfaces/system/types.ts b/packages/types/src/interfaces/system/types.ts
index 914591986c..f2e90e9770 100644
--- a/packages/types/src/interfaces/system/types.ts
+++ b/packages/types/src/interfaces/system/types.ts
@@ -1,9 +1,9 @@
 // Auto-generated via `yarn build:interfaces`, do not edit
 /* eslint-disable @typescript-eslint/no-empty-interface */
 
-import { Codec } from '@polkadot/types/types';
+import { Codec, ITuple } from '@polkadot/types/types';
 import { Enum, Option, Result, Struct, Vec } from '@polkadot/types/codec';
-import { Bytes, GenericEvent, Null, Text, u32, u8 } from '@polkadot/types/primitive';
+import { Bytes, GenericEvent, Text, u32, u8 } from '@polkadot/types/primitive';
 import { Digest, Hash } from '@polkadot/types/interfaces/runtime';
 
 /** Digest */
@@ -39,27 +39,31 @@ export interface DispatchErrorTo198 extends Struct {
   readonly error: u8;
 }
 
-/** Result<Null, DispatchError> */
-export interface DispatchResult extends Result<Null, DispatchError> {
+/** Result<ITuple<[]>, DispatchError> */
+export interface DispatchResult extends Result<ITuple<[]>, DispatchError> {
   /** Error:: (DispatchError) */
   readonly isError: boolean;
   /** DispatchError */
   readonly asError: DispatchError;
-  /** Ok::  */
+  /** Ok:: (()) */
   readonly isOk: boolean;
+  /** ITuple<[]> */
+  readonly asOk: ITuple<[]>;
 }
 
 /** DispatchResult */
 export interface DispatchResultOf extends DispatchResult {}
 
-/** Result<Null, Text> */
-export interface DispatchResultTo198 extends Result<Null, Text> {
+/** Result<ITuple<[]>, Text> */
+export interface DispatchResultTo198 extends Result<ITuple<[]>, Text> {
   /** Error:: (Text) */
   readonly isError: boolean;
   /** Text */
   readonly asError: Text;
-  /** Ok::  */
+  /** Ok:: (()) */
   readonly isOk: boolean;
+  /** ITuple<[]> */
+  readonly asOk: ITuple<[]>;
 }
 
 /** GenericEvent */
diff --git a/packages/types/src/primitive/Type.spec.ts b/packages/types/src/primitive/Type.spec.ts
index 1e50257f85..d602111335 100644
--- a/packages/types/src/primitive/Type.spec.ts
+++ b/packages/types/src/primitive/Type.spec.ts
@@ -65,10 +65,10 @@ describe('Type', (): void => {
     ).toEqual('(Bytes,(Balance,Balance),Vec<AccountId>)');
   });
 
-  it('changes () -> Null', (): void => {
+  it('changes () -> ()', (): void => {
     expect(
       new Type(registry, '()').toString()
-    ).toEqual('Null');
+    ).toEqual('()');
   });
 
   it('has a length for the type', (): void => {
diff --git a/packages/types/src/scripts/generateTypes/tsDef.ts b/packages/types/src/scripts/generateTypes/tsDef.ts
index 8d9309887d..7ee49a897c 100644
--- a/packages/types/src/scripts/generateTypes/tsDef.ts
+++ b/packages/types/src/scripts/generateTypes/tsDef.ts
@@ -19,6 +19,7 @@ interface Imports extends TypeImports {
 // helper to generate a `readonly <Name>: <Type>;` getter
 export function createGetter (definitions: object, name = '', type: string, imports: TypeImports, doc?: string): string {
   setImports(definitions, imports, [type]);
+
   return `  /** ${doc || type} */\n  readonly ${name}: ${type};\n`;
 }
 
@@ -61,14 +62,16 @@ function tsEnum (definitions: object, { name: enumName, sub }: TypeDef, imports:
   return exportInterface(enumName, 'Enum', keys.join(''));
 }
 
-function tsResultGetter (definitions: object, resultName = '', getter: 'Ok' | 'Error', { info, name = '', type }: TypeDef, imports: TypeImports): string {
+function tsResultGetter (definitions: object, resultName = '', getter: 'Ok' | 'Error', def: TypeDef, imports: TypeImports): string {
+  const { info, name = '', type } = def;
   const [resultType, asGetter] = type === 'Null'
     ? ['', '']
-    : [`(${type})`, createGetter(definitions, `as${getter}`, type, imports)];
+    : [`(${type})`, createGetter(definitions, `as${getter}`, info === TypeDefInfo.Tuple ? formatType(definitions, def, imports) : type, imports)];
   const isGetter = createGetter(definitions, `is${getter}`, 'boolean', imports, `${getter}:: ${name}${resultType}`);
 
   switch (info) {
     case TypeDefInfo.Plain:
+    case TypeDefInfo.Tuple:
     case TypeDefInfo.Vec:
       return `${isGetter}${asGetter}`;