diff --git a/CHANGELOG.md b/CHANGELOG.md
index aa401ad528..5dfa4aa84d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,17 @@
 # CHANGELOG
 
+## master
+
+Contributed:
+
+- Add `Range` & `RangeInclusive` types (Thanks to https://github.com/c410-f3r)
+- Always use TS `bigint` type (Thanks to https://github.com/ntduan)
+
+Changes:
+
+- Extend `createType` auto-TS decoration for `BreeMap`, `BTreeSet`, `HashMap`
+
+
 ## 5.4.1 Aug 9, 2021
 
 Upgrade priority: Low. Recommended for potential users of NMap.
diff --git a/packages/api-derive/src/session/types.ts b/packages/api-derive/src/session/types.ts
index 93e0b5f5a9..145b54d7a7 100644
--- a/packages/api-derive/src/session/types.ts
+++ b/packages/api-derive/src/session/types.ts
@@ -1,7 +1,7 @@
 // Copyright 2017-2021 @polkadot/api-derive authors & contributors
 // SPDX-License-Identifier: Apache-2.0
 
-import type { Option, u32 } from '@polkadot/types';
+import type { Option, u32, u64 } from '@polkadot/types';
 import type { BlockNumber, EraIndex, Moment, SessionIndex } from '@polkadot/types/interfaces';
 
 export interface DeriveSessionIndexes {
@@ -15,7 +15,7 @@ export interface DeriveSessionIndexes {
 export interface DeriveSessionInfo extends DeriveSessionIndexes {
   eraLength: BlockNumber;
   isEpoch: boolean;
-  sessionLength: BlockNumber;
+  sessionLength: u64;
   sessionsPerEra: SessionIndex;
 }
 
diff --git a/packages/types/src/checkTypes.manual.ts b/packages/types/src/checkTypes.manual.ts
index e14ca8cf77..be2c6b5cd7 100644
--- a/packages/types/src/checkTypes.manual.ts
+++ b/packages/types/src/checkTypes.manual.ts
@@ -48,11 +48,13 @@ const vv = registry.createType('Vec< Vec< Vec< Vec<u8>> > >');
 // vec with tuple
 const vt = registry.createType('Vec<(u8, u16)>');
 // nested stuff from all-over
-const vn = registry.createType('Vec<(u32, (u32, u64), Vec<u8>, Vec<(u32, u64)>, [u8;32], [u128;32])>');
+const vn = registry.createType('Vec<(u32, (u32, u64), Vec<u8>, Vec<u32>, Vec<(u32, u64)>, [u8;32], [u128;32])>');
 // nested fixed
 const nf = registry.createType('[[[u8;32];5];3]');
+// with linkage
+const tl = registry.createType('(ValidatorPrefsWithCommission, Linkage<AccountId>)');
 
-assert(ee[0].unwrap().unwrap().divn(123) && vb.unwrap().bitLength() && vv.toHuman() && vn.toHuman() && vt.toHuman() && nf.toHuman(), 'All ok');
+assert(ee[0].unwrap().unwrap().divn(123) && vb.unwrap().bitLength() && vv.toHuman() && vn[0][3][0].bitLength && vt.toHuman() && nf.toHuman() && tl[1].next, 'All ok');
 
 // tuple & struct
 const vs = registry.createType('(u8, {"a":"u32","b":"(u32,u64)"},(u8,u16),{"foo":"Bar"},u16)');
@@ -70,8 +72,10 @@ assert(gg.subarray(1), 'All ok');
 
 // Should end up as VecFixed<u128>
 const hh = registry.createType('[u128; 32]');
+// maps and sets
+const ms = registry.createType('(BTreeSet<u8>, BTreeMap<u16, u32>, HashMap<u64, u128>)');
 
-assert(hh[0].bitLength(), 'All ok');
+assert(hh[0].bitLength() && ms[0].strings && ms[1].values && ms[2].keys, 'All ok');
 
 // tuple! ITuple<[u32, Compact<u64>, u128, Codec]>
 const tt1 = registry.createType('(u32, Compact<u64>,    u128  , Something)');
diff --git a/packages/types/src/codec/BTreeSet.ts b/packages/types/src/codec/BTreeSet.ts
index 756645bf9e..4fa4aa8a48 100644
--- a/packages/types/src/codec/BTreeSet.ts
+++ b/packages/types/src/codec/BTreeSet.ts
@@ -2,7 +2,7 @@
 // SPDX-License-Identifier: Apache-2.0
 
 import type { CodecHash, Hash } from '../interfaces/runtime';
-import type { AnyJson, Codec, Constructor, Registry } from '../types';
+import type { AnyJson, Codec, Constructor, ISet, Registry } from '../types';
 
 import { compactFromU8a, compactToU8a, isHex, isU8a, logger, stringify, u8aConcat, u8aToHex, u8aToU8a } from '@polkadot/util';
 
@@ -76,7 +76,7 @@ function decodeSet<V extends Codec> (registry: Registry, valType: Constructor<V>
   throw new Error('BTreeSet: cannot decode type');
 }
 
-export class BTreeSet<V extends Codec = Codec> extends Set<V> implements Codec {
+export class BTreeSet<V extends Codec = Codec> extends Set<V> implements ISet<V> {
   public readonly registry: Registry;
 
   public createdAtHash?: Hash;
@@ -125,6 +125,13 @@ export class BTreeSet<V extends Codec = Codec> extends Set<V> implements Codec {
     return this.size === 0;
   }
 
+  /**
+   * @description The actual set values as a string[]
+   */
+  public get strings (): string[] {
+    return [...super.values()].map((v) => v.toString());
+  }
+
   /**
    * @description Compares the value of the input to see if there is a match
    */
diff --git a/packages/types/src/codec/Linkage.spec.ts b/packages/types/src/codec/Linkage.spec.ts
index 710d7bcb18..3bf66ca70e 100644
--- a/packages/types/src/codec/Linkage.spec.ts
+++ b/packages/types/src/codec/Linkage.spec.ts
@@ -1,8 +1,6 @@
 // Copyright 2017-2021 @polkadot/types authors & contributors
 // SPDX-License-Identifier: Apache-2.0
 
-import type { Codec, ITuple } from '../types';
-
 import { TypeRegistry } from '../create/registry';
 import { Linkage } from '.';
 
@@ -34,7 +32,7 @@ describe('Linkage', (): void => {
 
     // actual check
     expect(
-      registry.createType<ITuple<[Codec, Linkage<Codec>]>>(
+      registry.createType(
         '(ValidatorPrefsWithCommission, Linkage<AccountId>)',
         '0x0284d7170001da30b68f54f686f586ddb29de12b682dd8bd1404566fb8a8db5dec20aa5b6b36'
       ).toHuman()
diff --git a/packages/types/src/codec/Set.ts b/packages/types/src/codec/Set.ts
index 4b1f9ee7f7..59b70df173 100644
--- a/packages/types/src/codec/Set.ts
+++ b/packages/types/src/codec/Set.ts
@@ -74,7 +74,7 @@ function decodeSet (setValues: SetValues, value: string[] | Set<string> | Uint8A
  * An Set is an array of string values, represented an an encoded type by
  * a bitwise representation of the values.
  */
-export class CodecSet extends Set<string> implements ISet {
+export class CodecSet extends Set<string> implements ISet<string> {
   public readonly registry: Registry;
 
   public createdAtHash?: Hash;
diff --git a/packages/types/src/codec/index.ts b/packages/types/src/codec/index.ts
index abf8264218..64aee4e410 100644
--- a/packages/types/src/codec/index.ts
+++ b/packages/types/src/codec/index.ts
@@ -21,6 +21,8 @@ export { CodecMap, CodecMap as Map } from './Map';
 export { Option } from './Option';
 export { Raw } from './Raw';
 export { Result } from './Result';
+export { Range } from './Range';
+export { RangeInclusive } from './RangeInclusive';
 export { CodecSet, CodecSet as Set } from './Set';
 export { Struct } from './Struct';
 export { Tuple } from './Tuple';
@@ -29,5 +31,3 @@ export { U8aFixed } from './U8aFixed';
 export { Vec } from './Vec';
 // export { VecAny } from './VecAny';
 export { VecFixed } from './VecFixed';
-export { Range } from './Range';
-export { RangeInclusive } from './RangeInclusive';
diff --git a/packages/types/src/primitive/I128.ts b/packages/types/src/primitive/I128.ts
index cbc97f3f52..f798baf4c3 100644
--- a/packages/types/src/primitive/I128.ts
+++ b/packages/types/src/primitive/I128.ts
@@ -8,4 +8,7 @@ import { Int } from '../codec/Int';
  * @description
  * A 128-bit signed integer
  */
-export class i128 extends Int.with(128) {}
+export class i128 extends Int.with(128) {
+  // NOTE without this, we cannot properly determine extensions
+  public readonly __IntType = 'i128';
+}
diff --git a/packages/types/src/primitive/I16.ts b/packages/types/src/primitive/I16.ts
index 7cdbc9f631..17aa761b1a 100644
--- a/packages/types/src/primitive/I16.ts
+++ b/packages/types/src/primitive/I16.ts
@@ -8,4 +8,7 @@ import { Int } from '../codec/Int';
  * @description
  * A 16-bit signed integer
  */
-export class i16 extends Int.with(16) {}
+export class i16 extends Int.with(16) {
+  // NOTE without this, we cannot properly determine extensions
+  public readonly __IntType = 'i16';
+}
diff --git a/packages/types/src/primitive/I256.ts b/packages/types/src/primitive/I256.ts
index bad91a8b7d..5a45cf6205 100644
--- a/packages/types/src/primitive/I256.ts
+++ b/packages/types/src/primitive/I256.ts
@@ -8,4 +8,7 @@ import { Int } from '../codec/Int';
  * @description
  * A 256-bit signed integer
  */
-export class i256 extends Int.with(256) {}
+export class i256 extends Int.with(256) {
+  // NOTE without this, we cannot properly determine extensions
+  public readonly __IntType = 'i256';
+}
diff --git a/packages/types/src/primitive/I32.ts b/packages/types/src/primitive/I32.ts
index 7a99872bf4..ab1c489046 100644
--- a/packages/types/src/primitive/I32.ts
+++ b/packages/types/src/primitive/I32.ts
@@ -8,4 +8,7 @@ import { Int } from '../codec/Int';
  * @description
  * A 32-bit signed integer
  */
-export class i32 extends Int.with(32) {}
+export class i32 extends Int.with(32) {
+  // NOTE without this, we cannot properly determine extensions
+  public readonly __IntType = 'i32';
+}
diff --git a/packages/types/src/primitive/I64.ts b/packages/types/src/primitive/I64.ts
index e709a64770..f7a8626d77 100644
--- a/packages/types/src/primitive/I64.ts
+++ b/packages/types/src/primitive/I64.ts
@@ -8,4 +8,7 @@ import { Int } from '../codec/Int';
  * @description
  * A 64-bit signed integer
  */
-export class i64 extends Int.with(64) {}
+export class i64 extends Int.with(64) {
+  // NOTE without this, we cannot properly determine extensions
+  public readonly __IntType = 'i64';
+}
diff --git a/packages/types/src/primitive/I8.ts b/packages/types/src/primitive/I8.ts
index 082cb6c4f1..999c05059f 100644
--- a/packages/types/src/primitive/I8.ts
+++ b/packages/types/src/primitive/I8.ts
@@ -8,4 +8,7 @@ import { Int } from '../codec/Int';
  * @description
  * An 8-bit signed integer
  */
-export class i8 extends Int.with(8) {}
+export class i8 extends Int.with(8) {
+  // NOTE without this, we cannot properly determine extensions
+  public readonly __IntType = 'i8';
+}
diff --git a/packages/types/src/primitive/U128.ts b/packages/types/src/primitive/U128.ts
index 7460617075..39e9fdd006 100644
--- a/packages/types/src/primitive/U128.ts
+++ b/packages/types/src/primitive/U128.ts
@@ -8,4 +8,7 @@ import { UInt } from '../codec/UInt';
  * @description
  * A 128-bit unsigned integer
  */
-export class u128 extends UInt.with(128) {}
+export class u128 extends UInt.with(128) {
+  // NOTE without this, we cannot properly determine extensions
+  public readonly __UIntType = 'u128';
+}
diff --git a/packages/types/src/primitive/U16.ts b/packages/types/src/primitive/U16.ts
index 8da470c751..989603b2e4 100644
--- a/packages/types/src/primitive/U16.ts
+++ b/packages/types/src/primitive/U16.ts
@@ -8,4 +8,7 @@ import { UInt } from '../codec/UInt';
  * @description
  * A 16-bit unsigned integer
  */
-export class u16 extends UInt.with(16) {}
+export class u16 extends UInt.with(16) {
+  // NOTE without this, we cannot properly determine extensions
+  public readonly __UIntType = 'u16';
+}
diff --git a/packages/types/src/primitive/U256.ts b/packages/types/src/primitive/U256.ts
index 61351e8d56..caf0953b74 100644
--- a/packages/types/src/primitive/U256.ts
+++ b/packages/types/src/primitive/U256.ts
@@ -8,4 +8,7 @@ import { UInt } from '../codec/UInt';
  * @description
  * A 256-bit unsigned integer
  */
-export class u256 extends UInt.with(256) {}
+export class u256 extends UInt.with(256) {
+  // NOTE without this, we cannot properly determine extensions
+  public readonly __UIntType = 'u256';
+}
diff --git a/packages/types/src/primitive/U32.ts b/packages/types/src/primitive/U32.ts
index c79bbeaa79..b745c4d205 100644
--- a/packages/types/src/primitive/U32.ts
+++ b/packages/types/src/primitive/U32.ts
@@ -8,4 +8,7 @@ import { UInt } from '../codec/UInt';
  * @description
  * A 32-bit unsigned integer
  */
-export class u32 extends UInt.with(32) {}
+export class u32 extends UInt.with(32) {
+  // NOTE without this, we cannot properly determine extensions
+  public readonly __UIntType = 'u32';
+}
diff --git a/packages/types/src/primitive/U64.ts b/packages/types/src/primitive/U64.ts
index f684989b12..8899be99f3 100644
--- a/packages/types/src/primitive/U64.ts
+++ b/packages/types/src/primitive/U64.ts
@@ -8,4 +8,7 @@ import { UInt } from '../codec/UInt';
  * @description
  * A 64-bit unsigned integer
  */
-export class u64 extends UInt.with(64) {}
+export class u64 extends UInt.with(64) {
+  // NOTE without this, we cannot properly determine extensions
+  public readonly __UIntType = 'u64';
+}
diff --git a/packages/types/src/primitive/U8.ts b/packages/types/src/primitive/U8.ts
index 3af2ec57e4..bb1f8aa833 100644
--- a/packages/types/src/primitive/U8.ts
+++ b/packages/types/src/primitive/U8.ts
@@ -8,4 +8,7 @@ import { UInt } from '../codec/UInt';
  * @description
  * An 8-bit unsigned integer
  */
-export class u8 extends UInt.with(8) {}
+export class u8 extends UInt.with(8) {
+  // NOTE without this, we cannot properly determine extensions
+  public readonly __UIntType = 'u8';
+}
diff --git a/packages/types/src/types/detect.ts b/packages/types/src/types/detect.ts
index 86ee448bbc..8c7ac6c211 100644
--- a/packages/types/src/types/detect.ts
+++ b/packages/types/src/types/detect.ts
@@ -1,8 +1,8 @@
 // Copyright 2017-2021 @polkadot/types authors & contributors
 // SPDX-License-Identifier: Apache-2.0
 
-import type { Compact, Option, Raw, Vec, VecFixed } from '../codec';
-import type { Bytes, Null } from '../primitive';
+import type { BTreeMap, BTreeSet, CodecSet, Compact, Enum, HashMap, Linkage, Option, Raw, Struct, Vec, VecFixed } from '../codec';
+import type { Bytes, Null, u8 } from '../primitive';
 import type { Codec, Constructor } from './codec';
 import type { ICompact, IEnum, IMap, IMethod, INumber, IOption, IResult, ISet, IStruct, ITuple, IU8a, IVec } from './interfaces';
 import type { InterfaceTypes } from './registry';
@@ -14,11 +14,11 @@ export type DetectCodec<T extends Codec, K extends string> =
     ? InterfaceTypes[K]
     : T extends ICompact | IEnum | IMap | IMethod | INumber | IOption | IResult | ISet | IStruct | ITuple | IU8a | IVec
       ? T
-      : __ExtractCodec<__ToCodecs<__Tokenize<__Sanitize<K>>[0]>>;
+      : __Codec<__Codecs<__Tokenize<__Sanitize<K>>[0]>>;
 
 export type DetectConstructor<T extends Codec, K extends string> = Constructor<DetectCodec<T, K>>;
 
-export type __ExtractCodec<V extends Codec[]> =
+export type __Codec<V extends Codec[]> =
   V[0] extends Codec
     ? V[0]
     : Codec;
@@ -37,34 +37,34 @@ export type __Sanitize<K extends string> =
 
 export type __Value = string | Record<string, unknown> | __Value[];
 
-export type __ToCodec<K extends unknown, C extends Codec[], N extends unknown[]> =
-  K extends keyof InterfaceTypes
-    ? InterfaceTypes[K]
-    : K extends unknown[]
-      ? __ToTuple<__ToCodecs<K>>
-      : K extends Record<string, unknown>
-        ? K['_enum'] extends Record<string, unknown>
-          ? IEnum
-          : K['_set'] extends Record<string, unknown>
-            ? ISet
-            : IStruct
-        : K extends Set<unknown>
-          ? ISet
-          : K extends '['
-            ? N[0] extends 'u8'
-              ? Raw
-              : VecFixed<C[0]>
-            : K extends 'Vec<'
-              ? N[0] extends 'u8'
-                ? Bytes
-                : Vec<C[0]>
-              : K extends 'Option<'
-                ? Option<C[0]>
-                : K extends 'Compact<'
-                  ? C[0] extends INumber
-                    ? Compact<C[0]>
-                    : Codec
-                  : Codec;
+export type __MapWrapOne<C extends Codec> = {
+  'BTreeSet<': BTreeSet<C>;
+  'Compact<': C extends INumber ? Compact<C> : Codec;
+  'Linkage<': Linkage<C>;
+  'Option<': Option<C>;
+  'Vec<': C extends u8 ? Bytes : Vec<C>;
+  '[': C extends u8 ? Raw : VecFixed<C>;
+};
+
+// FIXME We don't cater for Int< & UInt< here. These could be problematic, since it has
+// a variable number of inner arguments, better would be to just strip them inside the sanitize
+export type __MapWrapTwo<K extends Codec, V extends Codec> = {
+  'BTreeMap<': BTreeMap<K, V>;
+  'HashMap<': HashMap<K, V>;
+};
+
+export type __WrapOne = keyof __MapWrapOne<Codec>;
+
+export type __WrapTwo = keyof __MapWrapTwo<Codec, Codec>;
+
+export type __Wrap = __WrapOne | __WrapTwo;
+
+export type __ToStruct<K extends Record<string, unknown>> =
+  K['_enum'] extends true
+    ? Enum
+    : K['_set'] extends true
+      ? CodecSet
+      : Struct;
 
 export type __ToTuple<O extends Codec[]> =
   O[0] extends Codec
@@ -73,48 +73,64 @@ export type __ToTuple<O extends Codec[]> =
       : O[0]
     : Null;
 
-export type __ToCodecsInner<K extends unknown, N extends unknown[], C extends Codec[]> =
-  K extends '[' | 'Vec<' | 'Option<' | 'Compact<'
-    ? C extends [Codec, ...infer X]
-      ? [__ToCodec<K, C, N>, ...X]
-      : never
-    : [__ToCodec<K, C, N>, ...C];
+export type __CodecFirst<K extends unknown, C extends Codec[], X extends unknown[]> = [
+  K extends keyof InterfaceTypes
+    ? InterfaceTypes[K]
+    : K extends unknown[]
+      ? __ToTuple<__Codecs<K>>
+      : K extends Record<string, unknown>
+        ? __ToStruct<K>
+        : K extends __WrapOne
+          ? __MapWrapOne<C[0]>[K]
+          : K extends __WrapTwo
+            ? __MapWrapTwo<C[0], C[1]>[K]
+            : Codec,
+  ...X
+];
 
-export type __ToCodecs<T extends unknown[]> =
-  T extends [infer K, ...infer O]
-    ? __ToCodecsInner<K, O, __ToCodecs<O>>
+export type __CodecsNext<K extends unknown, C extends Codec[]> =
+  K extends __WrapOne
+    ? C extends [Codec, ...infer X]
+      ? __CodecFirst<K, C, X>
+      : never
+    : K extends __WrapTwo
+      ? C extends [Codec, Codec, ...infer X]
+        ? __CodecFirst<K, C, X>
+        : never
+      : __CodecFirst<K, C, C>;
+
+export type __Codecs<T extends unknown[]> =
+  T extends [infer K, ...infer N]
+    ? __CodecsNext<K, __Codecs<N>>
     : [];
 
-export type __RemoveEmpty<T extends string> =
-  T extends ''
-    ? []
-    : [T];
-
-export type __Combine<V extends __Value[], I extends string = '', T extends string = ''> =
-  [...V, ...__RemoveEmpty<I>, ...__RemoveEmpty<T>];
+export type __Combine<V extends __Value[], I extends string> =
+  I extends ''
+    ? V
+    : [...V, I];
 
 export type __CombineInner<V extends __Value[], I extends string, X extends __Value> =
-  [...__RemoveEmpty<I>, ...V, X];
+  I extends ''
+    ? [...V, X]
+    : [I, ...V, X];
 
-// TODO At this point structs are fully empty, no field indicators
+// FIXME At this point enum/set/struct are empty, no field indicators, just type indicators
 export type __TokenizeStruct<T extends [__Value[], string], V extends __Value[], I extends string, R extends string> =
-  __Tokenize<T[1], __CombineInner<V, I,
-  R extends `"_set"${string}`
-    // eslint-disable-next-line @typescript-eslint/ban-types
-    ? { _set: {} }
+  __Tokenize<T[1], __CombineInner<V, I, R extends `"_set"${string}`
+    ? { _set: true }
     : R extends `"_enum"${string}`
-      // eslint-disable-next-line @typescript-eslint/ban-types
-      ? { _enum: {} }
-      // eslint-disable-next-line @typescript-eslint/ban-types
-      : { data: R }
+      ? { _enum: true }
+      : { _fields: true }
   >>;
 
 export type __TokenizeTuple<T extends [__Value[], string], V extends __Value[], I extends string> =
   __Tokenize<T[1], __CombineInner<V, I, T[0]>>;
 
-export type __TokenizeWrapper<K extends string, V extends __Value[], I extends string, R extends string> =
+export type __TokenizeWrapped<K extends string, V extends __Value[], I extends string, R extends string> =
   K extends `${infer X}${R}`
-    ? __Tokenize<R, __Combine<V, `${I}${X}`>>
+    ? X extends '['
+      ? __Tokenize<R, [...__Combine<V, I>, '[']>
+      : __Tokenize<R, __Combine<V, `${I}${X}`>>
     : never;
 
 export type __TokenizeKnown<K extends string, V extends __Value[], I extends string, R extends string> =
@@ -127,20 +143,18 @@ export type __TokenizeKnown<K extends string, V extends __Value[], I extends str
 export type __Tokenize<K extends string, V extends __Value[] = [], I extends string = ''> =
   K extends '' | ')' | '>' | '}'
     ? [__Combine<V, I>, '']
-    : K extends `${'Vec<' | 'Option<' | 'Compact<'}${infer R}`
-      ? __TokenizeWrapper<K, V, I, R>
+    : K extends `${__Wrap}${infer R}`
+      ? __TokenizeWrapped<K, V, I, R>
       : K extends `${',' | '>'}${infer R}`
         ? __Tokenize<R, __Combine<V, I>>
-        : K extends `[${infer R}`
-          ? __Tokenize<R, __Combine<V, I, '['>>
-          : K extends `)${infer R}` | `}${infer R}`
-            ? [__Combine<V, I>, R]
-            : K extends `(${infer R}`
-              ? __TokenizeTuple<__Tokenize<R>, V, I>
-              : K extends `{${infer R}`
-                ? __TokenizeStruct<__Tokenize<R>, V, I, R>
-                : K extends `${keyof InterfaceTypes}${',' | '>'}${infer R}`
-                  ? __TokenizeKnown<K, V, I, R>
-                  : K extends `${infer C}${infer R}`
-                    ? __Tokenize<R, V, `${I}${C}`>
-                    : [__Combine<V, I>, ''];
+        : K extends `)${infer R}` | `}${infer R}`
+          ? [__Combine<V, I>, R]
+          : K extends `(${infer R}`
+            ? __TokenizeTuple<__Tokenize<R>, V, I>
+            : K extends `{${infer R}`
+              ? __TokenizeStruct<__Tokenize<R>, V, I, R>
+              : K extends `${keyof InterfaceTypes}${',' | '>'}${infer R}`
+                ? __TokenizeKnown<K, V, I, R>
+                : K extends `${infer C}${infer R}`
+                  ? __Tokenize<R, V, `${I}${C}`>
+                  : [__Combine<V, I>, ''];
diff --git a/packages/types/src/types/interfaces.ts b/packages/types/src/types/interfaces.ts
index b915535e53..7f663ccff1 100644
--- a/packages/types/src/types/interfaces.ts
+++ b/packages/types/src/types/interfaces.ts
@@ -53,7 +53,6 @@ export interface IResult<O extends Codec = Codec, E extends Codec = Codec> exten
 
 export interface ISet<K = string> extends Set<K>, Codec {
   readonly strings: string[];
-  readonly valueEncoded: BN;
 }
 
 export interface IStruct<K = string, V extends Codec = Codec> extends Map<K, V>, Codec {