diff --git a/src/spectator/mocks/exception_method_stub.cr b/src/spectator/mocks/exception_method_stub.cr
index 2f223fd..ce34b64 100644
--- a/src/spectator/mocks/exception_method_stub.cr
+++ b/src/spectator/mocks/exception_method_stub.cr
@@ -7,7 +7,7 @@ module Spectator::Mocks
       super(name, location, args)
     end
 
-    def call(_args : GenericArguments(T, NT), &_original : -> RT) forall T, NT, RT
+    def call(_args : GenericArguments(T, NT), & : -> RT) forall T, NT, RT
       raise @exception
     end
   end
diff --git a/src/spectator/mocks/method_stub.cr b/src/spectator/mocks/method_stub.cr
index 9ad78a3..bf9d0e6 100644
--- a/src/spectator/mocks/method_stub.cr
+++ b/src/spectator/mocks/method_stub.cr
@@ -14,9 +14,9 @@ module Spectator::Mocks
       @name == call.name
     end
 
-    abstract def call(args : GenericArguments(T, NT), &original : -> RT) forall T, NT, RT
+    abstract def call(args : GenericArguments(T, NT), & : -> RT) forall T, NT, RT
 
-    def call!(args : GenericArguments(T, NT), &original : -> RT) : RT forall T, NT, RT
+    def call!(args : GenericArguments(T, NT), & : -> RT) : RT forall T, NT, RT
       value = call(args) { |*ya| yield *ya }
       if value.is_a?(RT)
         value.as(RT)
diff --git a/src/spectator/mocks/multi_value_method_stub.cr b/src/spectator/mocks/multi_value_method_stub.cr
index f025271..944e985 100644
--- a/src/spectator/mocks/multi_value_method_stub.cr
+++ b/src/spectator/mocks/multi_value_method_stub.cr
@@ -10,7 +10,7 @@ module Spectator::Mocks
       raise ArgumentError.new("Values must have at least one item") if @values.size < 1
     end
 
-    def call(_args : GenericArguments(T, NT), &_original : -> RT) forall T, NT, RT
+    def call(_args : GenericArguments(T, NT), & : -> RT) forall T, NT, RT
       value = @values[@index]
       @index += 1 if @index < @values.size - 1
       value
diff --git a/src/spectator/mocks/nil_method_stub.cr b/src/spectator/mocks/nil_method_stub.cr
index 1e87db6..38b1aab 100644
--- a/src/spectator/mocks/nil_method_stub.cr
+++ b/src/spectator/mocks/nil_method_stub.cr
@@ -4,7 +4,7 @@ require "./value_method_stub"
 
 module Spectator::Mocks
   class NilMethodStub < GenericMethodStub(Nil)
-    def call(_args : GenericArguments(T, NT), &_original : -> RT) forall T, NT, RT
+    def call(_args : GenericArguments(T, NT), & : -> RT) forall T, NT, RT
       nil
     end
 
diff --git a/src/spectator/mocks/original_method_stub.cr b/src/spectator/mocks/original_method_stub.cr
index 2097eb6..041325a 100644
--- a/src/spectator/mocks/original_method_stub.cr
+++ b/src/spectator/mocks/original_method_stub.cr
@@ -3,7 +3,7 @@ require "./generic_method_stub"
 
 module Spectator::Mocks
   class OriginalMethodStub < GenericMethodStub(Nil)
-    def call(_args : GenericArguments(T, NT), &_original : -> RT) forall T, NT, RT
+    def call(_args : GenericArguments(T, NT), & : -> RT) forall T, NT, RT
       yield
     end
   end
diff --git a/src/spectator/mocks/proc_method_stub.cr b/src/spectator/mocks/proc_method_stub.cr
index de3a68d..a72eb3c 100644
--- a/src/spectator/mocks/proc_method_stub.cr
+++ b/src/spectator/mocks/proc_method_stub.cr
@@ -11,7 +11,7 @@ module Spectator::Mocks
       ProcMethodStub.new(name, location, block, args)
     end
 
-    def call(_args : GenericArguments(T, NT), &_original : -> RT) forall T, NT, RT
+    def call(_args : GenericArguments(T, NT), & : -> RT) forall T, NT, RT
       @proc.call
     end
   end
diff --git a/src/spectator/mocks/value_method_stub.cr b/src/spectator/mocks/value_method_stub.cr
index d3e7f5e..cda6b22 100644
--- a/src/spectator/mocks/value_method_stub.cr
+++ b/src/spectator/mocks/value_method_stub.cr
@@ -7,7 +7,7 @@ module Spectator::Mocks
       super(name, location, args)
     end
 
-    def call(_args : GenericArguments(T, NT), &_original : -> RT) forall T, NT, RT
+    def call(_args : GenericArguments(T, NT), & : -> RT) forall T, NT, RT
       @value
     end
   end