diff --git a/.travis.yml b/.travis.yml
index b3c8e352e..b9d2c1479 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -17,7 +17,7 @@ sudo: false
 env:
   global:
     # If changing this number, please also change it in `test/test_helper.rb`.
-    - STRIPE_MOCK_VERSION=0.79.0
+    - STRIPE_MOCK_VERSION=0.88.0
 
 cache:
   directories:
diff --git a/lib/stripe/object_types.rb b/lib/stripe/object_types.rb
index c0800581a..cd685d3d8 100644
--- a/lib/stripe/object_types.rb
+++ b/lib/stripe/object_types.rb
@@ -19,6 +19,7 @@ def self.object_names_to_classes
         Balance::OBJECT_NAME => Balance,
         BalanceTransaction::OBJECT_NAME => BalanceTransaction,
         BankAccount::OBJECT_NAME => BankAccount,
+        BillingPortal::Session::OBJECT_NAME => BillingPortal::Session,
         BitcoinReceiver::OBJECT_NAME => BitcoinReceiver,
         BitcoinTransaction::OBJECT_NAME => BitcoinTransaction,
         Capability::OBJECT_NAME => Capability,
diff --git a/lib/stripe/resources.rb b/lib/stripe/resources.rb
index dd76ea691..fc58b8d01 100644
--- a/lib/stripe/resources.rb
+++ b/lib/stripe/resources.rb
@@ -9,6 +9,7 @@
 require "stripe/resources/balance"
 require "stripe/resources/balance_transaction"
 require "stripe/resources/bank_account"
+require "stripe/resources/billing_portal/session"
 require "stripe/resources/bitcoin_receiver"
 require "stripe/resources/bitcoin_transaction"
 require "stripe/resources/capability"
diff --git a/lib/stripe/resources/billing_portal/session.rb b/lib/stripe/resources/billing_portal/session.rb
new file mode 100644
index 000000000..058706635
--- /dev/null
+++ b/lib/stripe/resources/billing_portal/session.rb
@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+module Stripe
+  module BillingPortal
+    class Session < APIResource
+      extend Stripe::APIOperations::Create
+
+      OBJECT_NAME = "billing_portal.session"
+    end
+  end
+end
diff --git a/test/stripe/billing_portal/session_test.rb b/test/stripe/billing_portal/session_test.rb
new file mode 100644
index 000000000..440279a58
--- /dev/null
+++ b/test/stripe/billing_portal/session_test.rb
@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+require ::File.expand_path("../../test_helper", __dir__)
+
+module Stripe
+  module BillingPortal
+    class SessionTest < Test::Unit::TestCase
+      should "be creatable" do
+        session = Stripe::BillingPortal::Session.create(
+          customer: "cus_123",
+          return_url: "https://stripe.com/return"
+        )
+        assert_requested :post, "#{Stripe.api_base}/v1/billing_portal/sessions"
+        assert session.is_a?(Stripe::BillingPortal::Session)
+      end
+    end
+  end
+end
diff --git a/test/stripe/issuing/card_test.rb b/test/stripe/issuing/card_test.rb
index f0d998d8a..a493b141c 100644
--- a/test/stripe/issuing/card_test.rb
+++ b/test/stripe/issuing/card_test.rb
@@ -43,6 +43,10 @@ class CardTest < Test::Unit::TestCase
 
       context "#details" do
         should "retrieve a card's details" do
+          # The /details endpoint is deprecated and not in the spec so we mock
+          stub_request(:get, "#{Stripe.api_base}/v1/issuing/cards/ic_123/details")
+            .to_return(body: JSON.generate(object: "issuing.card_details"))
+
           card_details = Stripe::Issuing::Card.details("ic_123")
           assert_requested :get, "#{Stripe.api_base}/v1/issuing/cards/ic_123/details"
           assert card_details.is_a?(Stripe::Issuing::CardDetails)
@@ -51,8 +55,16 @@ class CardTest < Test::Unit::TestCase
 
       context ".details" do
         should "retrieve a card's details" do
-          card = Stripe::Issuing::Card.retrieve("ic_123")
+          # The /details endpoint is deprecated and not in the spec so we mock
+          stub_request(:get, "#{Stripe.api_base}/v1/issuing/cards/ic_123/details")
+            .to_return(body: JSON.generate(object: "issuing.card_details"))
+
+          card = Stripe::Issuing::Card.construct_from(
+            id: "ic_123",
+            object: "issuing.card_details"
+          )
           card_details = card.details
+
           assert_requested :get, "#{Stripe.api_base}/v1/issuing/cards/ic_123/details"
           assert card_details.is_a?(Stripe::Issuing::CardDetails)
         end
diff --git a/test/stripe/issuing/dispute_test.rb b/test/stripe/issuing/dispute_test.rb
index 2d0e27509..33d6b0733 100644
--- a/test/stripe/issuing/dispute_test.rb
+++ b/test/stripe/issuing/dispute_test.rb
@@ -6,10 +6,8 @@ module Stripe
   module Issuing
     class DisputeTest < Test::Unit::TestCase
       should "be creatable" do
-        dispute = Stripe::Issuing::Dispute.create(
-          reason: "fraudulent",
-          disputed_transaction: "ipi_123"
-        )
+        dispute = Stripe::Issuing::Dispute.create
+
         assert_requested :post, "#{Stripe.api_base}/v1/issuing/disputes"
         assert dispute.is_a?(Stripe::Issuing::Dispute)
       end
@@ -27,16 +25,8 @@ class DisputeTest < Test::Unit::TestCase
         assert dispute.is_a?(Stripe::Issuing::Dispute)
       end
 
-      should "be saveable" do
-        dispute = Stripe::Issuing::Dispute.retrieve("ich_123")
-        dispute.metadata["key"] = "value"
-        dispute.save
-        assert_requested :post, "#{Stripe.api_base}/v1/issuing/disputes/#{dispute.id}"
-        assert dispute.is_a?(Stripe::Issuing::Dispute)
-      end
-
       should "be updateable" do
-        dispute = Stripe::Issuing::Dispute.update("ich_123", metadata: { foo: "bar" })
+        dispute = Stripe::Issuing::Dispute.update("ich_123", {})
         assert_requested :post, "#{Stripe.api_base}/v1/issuing/disputes/ich_123"
         assert dispute.is_a?(Stripe::Issuing::Dispute)
       end
diff --git a/test/test_helper.rb b/test/test_helper.rb
index 965982397..80b079a0d 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -16,7 +16,7 @@
 require ::File.expand_path("stripe_mock", __dir__)
 
 # If changing this number, please also change it in `.travis.yml`.
-MOCK_MINIMUM_VERSION = "0.79.0"
+MOCK_MINIMUM_VERSION = "0.88.0"
 MOCK_PORT = Stripe::StripeMock.start
 
 # Disable all real network connections except those that are outgoing to