diff --git a/lib/mutant/mutator/literal/boolean.rb b/lib/mutant/mutator/literal/boolean.rb
index d0bbe5dd..625bfc18 100644
--- a/lib/mutant/mutator/literal/boolean.rb
+++ b/lib/mutant/mutator/literal/boolean.rb
@@ -27,7 +27,7 @@ module Mutant
           new(self.class::INVERSE_CLASS)
         end
 
-        # Represent mutations of true literal
+        # Mutator for true literals
         class TrueLiteral < self
           INVERSE_CLASS = Rubinius::AST::FalseLiteral
 
@@ -35,7 +35,7 @@ module Mutant
         end
 
 
-        # Represent mutations of false literal
+        # Mutator for false literals
         class FalseLiteral < self
           INVERSE_CLASS = Rubinius::AST::TrueLiteral
 
diff --git a/lib/mutant/mutator/literal/dynamic.rb b/lib/mutant/mutator/literal/dynamic.rb
index f99c5807..01b5f59a 100644
--- a/lib/mutant/mutator/literal/dynamic.rb
+++ b/lib/mutant/mutator/literal/dynamic.rb
@@ -3,6 +3,7 @@ module Mutant
     class Literal
       # Abstract mutations on dynamic literals
       class Dynamic < self
+        include AbstractType
 
       private
 
diff --git a/lib/mutant/mutator/literal/fixnum.rb b/lib/mutant/mutator/literal/fixnum.rb
index 5f2cf044..68225f11 100644
--- a/lib/mutant/mutator/literal/fixnum.rb
+++ b/lib/mutant/mutator/literal/fixnum.rb
@@ -1,7 +1,7 @@
 module Mutant
   class Mutator
     class Literal < self
-      # Represent mutations on fixnum literal
+      # Mutator for fixnum literals
       class Fixnum < self
 
         handle(Rubinius::AST::FixnumLiteral)
diff --git a/lib/mutant/mutator/literal/float.rb b/lib/mutant/mutator/literal/float.rb
index 1ec797fa..5ea2423b 100644
--- a/lib/mutant/mutator/literal/float.rb
+++ b/lib/mutant/mutator/literal/float.rb
@@ -1,7 +1,7 @@
 module Mutant
   class Mutator
     class Literal < self
-      # Represent mutations on fixnum literal
+      # Mutator for float literals
       class Float < self
 
         handle(Rubinius::AST::FloatLiteral)
diff --git a/lib/mutant/mutator/literal/hash.rb b/lib/mutant/mutator/literal/hash.rb
index 6795ce9f..d56812d7 100644
--- a/lib/mutant/mutator/literal/hash.rb
+++ b/lib/mutant/mutator/literal/hash.rb
@@ -1,7 +1,7 @@
 module Mutant
   class Mutator
-      class Literal
-      # Mutator for hash literal AST nodes
+    class Literal
+      # Mutator for hash literals
       class Hash < self
 
         handle(Rubinius::AST::HashLiteral)
diff --git a/lib/mutant/mutator/literal/nil.rb b/lib/mutant/mutator/literal/nil.rb
new file mode 100644
index 00000000..4ef36ea3
--- /dev/null
+++ b/lib/mutant/mutator/literal/nil.rb
@@ -0,0 +1,23 @@
+module Mutant
+  class Mutator
+    class Literal
+      # Mutator for nil literals
+      class Nil < self
+
+        handle(Rubinius::AST::NilLiteral)
+
+      private
+
+        # Emit mutants
+        #
+        # @return [undefined]
+        #
+        # @api private
+        #
+        def dispatch
+          emit('Object.new'.to_ast)
+        end
+      end
+    end
+  end
+end
diff --git a/lib/mutant/mutator/literal/regex.rb b/lib/mutant/mutator/literal/regex.rb
index a60922c6..e927dea3 100644
--- a/lib/mutant/mutator/literal/regex.rb
+++ b/lib/mutant/mutator/literal/regex.rb
@@ -1,7 +1,7 @@
 module Mutant
   class Mutator
     class Literal < self
-      # Mutator for regexp literal AST nodes
+      # Mutator for regexp literals
       class Regex < self
 
         handle(Rubinius::AST::RegexLiteral)
diff --git a/lib/mutant/mutator/literal/string.rb b/lib/mutant/mutator/literal/string.rb
index f88b0b4b..d58d3d4e 100644
--- a/lib/mutant/mutator/literal/string.rb
+++ b/lib/mutant/mutator/literal/string.rb
@@ -1,7 +1,7 @@
 module Mutant
   class Mutator
     class Literal
-      # Represent mutations on string literal
+      # Mutator for string literals
       class String < self
 
         handle(Rubinius::AST::StringLiteral)
diff --git a/lib/mutant/mutator/literal/symbol.rb b/lib/mutant/mutator/literal/symbol.rb
index 573ab8b3..6a2bfe63 100644
--- a/lib/mutant/mutator/literal/symbol.rb
+++ b/lib/mutant/mutator/literal/symbol.rb
@@ -1,7 +1,7 @@
 module Mutant
   class Mutator
     class Literal < self
-      # Represent mutations on symbol literal
+      # Mutator for symbol literals
       class Symbol < self
 
         handle(Rubinius::AST::SymbolLiteral)