diff --git a/lib/ui/command.rb b/lib/ui/command.rb
index e07de8c..3a8ec8e 100644
--- a/lib/ui/command.rb
+++ b/lib/ui/command.rb
@@ -1,5 +1,20 @@
 class IMICFPS
   class Commands
+    module Style
+      def self.error(string)
+        "<c=ff5555>#{string}</c>"
+      end
+      def self.warn(string)
+        "<c=ff5500>#{string}</c>"
+      end
+      def self.notice(string)
+        "<c=55ff55>#{string}</c>"
+      end
+      def self.highlight(string, color = "5555ff")
+        "<c=#{color}>#{string}</c>"
+      end
+    end
+
     class Command
       def self.inherited(subclass)
         @list ||= []
@@ -21,10 +36,39 @@ class IMICFPS
         if found_command
           found_command.handle(arguments, console)
         else
-          console.stdin("Command <c=ff5555>#{command}</c> not found.")
+          console.stdin("Command #{Style.error(command)} not found.")
         end
       end
 
+      def self.find(command)
+        @commands.detect { |cmd| cmd.command == command.to_sym }
+      end
+
+      def self.list_commands
+        @commands
+      end
+
+      def initialize
+        @store = {}
+        @subcommands = []
+
+        setup
+      end
+
+      def setup; end
+
+      def subcommand(command, type)
+        @subcommands << SubCommand.new(self, command, type)
+      end
+
+      def get(key)
+        @store.dig(key)
+      end
+
+      def set(key, value)
+        @store[key] = value
+      end
+
       def group
         raise NotImplementedError
       end
@@ -37,9 +81,95 @@ class IMICFPS
         raise NotImplementedError
       end
 
+      def handle_subcommand(arguments, console)
+        if arguments.size == 0
+          console.stdin(usage)
+          return
+        end
+        subcommand = arguments.delete_at(0)
+
+        found_command = @subcommands.detect { |cmd| cmd.command == subcommand.to_sym }
+        if found_command
+          found_command.handle(arguments, console)
+        else
+          console.stdin("Unknown subcommand #{Style.error(subcommand)} for #{Style.highlight(command)}")
+        end
+      end
+
       def usage
         raise NotImplementedError
       end
     end
+
+    class SubCommand
+      def initialize(parent, command, type)
+        @parent = parent
+        @command = command
+        @type = type
+      end
+
+      def command
+        @command
+      end
+
+      def handle(arguments, console)
+        case @type
+        when :boolean
+          case arguments.last
+          when "", nil
+            var = @parent.get(command.to_sym) ? @parent.get(command.to_sym) : false
+            console.stdin("#{command}: #{Style.highlight(var)}")
+          when "on"
+            var = @parent.set(command.to_sym, true)
+            console.stdin("#{command} => #{Style.highlight(var)}")
+          when "off"
+            var = @parent.set(command.to_sym, false)
+            console.stdin("#{command} => #{Style.highlight(var)}")
+          end
+        when :string
+          case arguments.last
+          when "", nil
+            var = @parent.get(command.to_sym) ? @parent.get(command.to_sym) : "\"\""
+            console.stdin("#{command}: #{Style.highlight(var)}")
+          else
+            var = @parent.set(command.to_sym, arguments.last)
+            console.stdin("#{command} => #{Style.highlight(var)}")
+          end
+        when :integer
+          case arguments.last
+          when "", nil
+            var = @parent.get(command.to_sym) ? @parent.get(command.to_sym) : "nil"
+            console.stdin("#{command}: #{Style.highlight(var)}")
+          else
+            var = @parent.set(command.to_sym, arguments.last.to_i)
+            console.stdin("#{command} => #{Style.highlight(var)}")
+          end
+        when :decimal
+          case arguments.last
+          when "", nil
+            var = @parent.get(command.to_sym) ? @parent.get(command.to_sym) : "nil"
+            console.stdin("#{command}: #{Style.highlight(var)}")
+          else
+            var = @parent.set(command.to_sym, arguments.last.to_f)
+            console.stdin("#{command} => #{Style.highlight(var)}")
+          end
+        else
+          raise RuntimeError
+        end
+      end
+
+      def usage
+        case @type
+        when :boolean
+          "#{Style.highlight(command)} #{Style.notice("[on|off]")}"
+        when :string
+          "#{Style.highlight(command)} #{Style.notice("[on|off]")}"
+        when :integer
+          "#{Style.highlight(command)} #{Style.notice("[on|off]")}"
+        when :decimal
+          "#{Style.highlight(command)} #{Style.notice("[on|off]")}"
+        end
+      end
+    end
   end
 end
\ No newline at end of file
diff --git a/lib/ui/commands/debug_command.rb b/lib/ui/commands/debug_command.rb
new file mode 100644
index 0000000..6c1873c
--- /dev/null
+++ b/lib/ui/commands/debug_command.rb
@@ -0,0 +1,31 @@
+class IMICFPS
+  class Commands
+    class DebugCommand < Command
+      def group
+        :global
+      end
+
+      def command
+        :debug
+      end
+
+      def setup
+        subcommand(:boundingboxes, :boolean)
+        subcommand(:wireframe, :boolean)
+        subcommand(:fps, :boolean)
+        subcommand(:stats, :boolean)
+        subcommand(:motd, :string)
+        subcommand(:mode, :integer)
+        subcommand(:gravity, :decimal)
+      end
+
+      def handle(arguments, console)
+        handle_subcommand(arguments, console)
+      end
+
+      def usage
+        string = "debug\n    #{@subcommands.map { |sub| sub.usage }.join("\n    ")}"
+      end
+    end
+  end
+end
\ No newline at end of file
diff --git a/lib/ui/commands/help_command.rb b/lib/ui/commands/help_command.rb
index 6179f2b..0650bc0 100644
--- a/lib/ui/commands/help_command.rb
+++ b/lib/ui/commands/help_command.rb
@@ -1,9 +1,6 @@
 class IMICFPS
   class Commands
     class HelpCommand < Command
-      def initialize
-      end
-
       def group
         :global
       end
@@ -13,11 +10,17 @@ class IMICFPS
       end
 
       def handle(arguments, console)
-        console.stdin(usage)
+        console.stdin(usage(arguments.first))
       end
 
-      def usage
-        "HELP\ncommand [arguments]\ncommand subcommand [argument]"
+      def usage(command = nil)
+        if command
+          if cmd = Command.find(command)
+            cmd.usage
+          end
+        else
+          "Available commands:\n#{Command.list_commands.map { |cmd| "#{Style.highlight(cmd.command)}" }.join(', ')}"
+        end
       end
     end
   end