diff --git a/Sources/Public/Clients/AmiiboMockClient.swift b/Sources/Public/Clients/AmiiboMockClient.swift
index bf90c65..dbcb754 100644
--- a/Sources/Public/Clients/AmiiboMockClient.swift
+++ b/Sources/Public/Clients/AmiiboMockClient.swift
@@ -19,6 +19,7 @@ public struct AmiiboMockClient {
     private let amiibos: [Amiibo]?
     private let amiiboSeries: [AmiiboSeries]?
     private let amiiboTypes: [AmiiboType]?
+    private let error: AmiiboServiceError?
     private let gameCharacters: [GameCharacter]?
     private let gameSeries: [GameSeries]?
     private let lastUpdated: Date?
@@ -31,11 +32,13 @@ public struct AmiiboMockClient {
         amiiboTypes: [AmiiboType]? = nil,
         gameCharacters: [GameCharacter]? = nil,
         gameSeries: [GameSeries]? = nil,
-        lastUpdated: Date? = nil
+        lastUpdated: Date? = nil,
+        error: AmiiboServiceError? = nil
     ) {
         self.amiibos = amiibos
         self.amiiboSeries = amiiboSeries
         self.amiiboTypes = amiiboTypes
+        self.error = error
         self.gameCharacters = gameCharacters
         self.gameSeries = gameSeries
         self.lastUpdated = lastUpdated
@@ -50,6 +53,8 @@ extension AmiiboMockClient: APIClient {
     // MARK: Functions
 
     public func getAmiibos(by filter: AmiiboFilter) async throws -> [Amiibo] {
+        try throwErrorIfExists()
+
         guard let amiibos else {
             throw AmiiboServiceError.notFound
         }
@@ -58,6 +63,8 @@ extension AmiiboMockClient: APIClient {
     }
     
     public func getAmiiboSeries(by filter: AmiiboSeriesFilter) async throws -> [AmiiboSeries] {
+        try throwErrorIfExists()
+
         guard let amiiboSeries else {
             throw AmiiboServiceError.notFound
         }
@@ -66,6 +73,8 @@ extension AmiiboMockClient: APIClient {
     }
     
     public func getAmiiboTypes(by filter: AmiiboTypeFilter) async throws -> [AmiiboType] {
+        try throwErrorIfExists()
+
         guard let amiiboTypes else {
             throw AmiiboServiceError.notFound
         }
@@ -74,6 +83,8 @@ extension AmiiboMockClient: APIClient {
     }
     
     public func getGameCharacters(by filter: GameCharacterFilter) async throws -> [GameCharacter] {
+        try throwErrorIfExists()
+
         guard let gameCharacters else {
             throw AmiiboServiceError.notFound
         }
@@ -82,6 +93,8 @@ extension AmiiboMockClient: APIClient {
     }
     
     public func getGameSeries(by filter: GameSeriesFilter) async throws -> [GameSeries] {
+        try throwErrorIfExists()
+
         guard let gameSeries else {
             throw AmiiboServiceError.notFound
         }
@@ -90,6 +103,8 @@ extension AmiiboMockClient: APIClient {
     }
     
     public func getLastUpdated() async throws -> Date {
+        try throwErrorIfExists()
+
         guard let lastUpdated else {
             throw AmiiboServiceError.notFound
         }
@@ -99,3 +114,17 @@ extension AmiiboMockClient: APIClient {
     
     
 }
+
+// MARK: - Helpers
+
+private extension AmiiboMockClient {
+    
+    // MARK: Functions
+    
+    func throwErrorIfExists() throws {
+        if let error {
+            throw error
+        }
+    }
+    
+}