If you try to collect an item just west of Amber City under a tree you will get

Script 'Interpreter' Line 276: RuntimeError occurred.

Script error within event 3, map 223 (Amber City):

Exception: NameError

Message: (eval):in pbExecuteScript uninitialized constant

PDitems::XDEFEND

***Full Script:

Kernel.pbItemBall (PBItems::XDEFEND)

interpreter:243:in pbExcuteScript

interpreter:794:in Eval

interpreter:243:in pbExecuteScript

interpreter:794: in command_111

interpreter:320:in execute_command

interpreter:193:in update

interpreter:106:in loop

interpreter:198:in update

Scene_Map:103: in update

Scene_Map:101:in loop