Wizard Cromperty is a wizard-inventor living in the northeast corner of East Ardougne. He has a very friendly attitude and uses a somewhat comic manner of speaking. He also tends to start thinking about different inventions during dialogues (quests dialogues that is) and forgetting about the player presence, giving an absent-minded attitude.
While having two jobs, he creates magic inventions. His best invention to date is his patented pending teleport block, a pair of blocks teleporting the user from one block to another. Hoping to demonstrate it to the staff at the Wizards' Tower, he sent the package to the RPDT Postal Service to deliver it. The package is never delivered and the player can interchange the address label of the crate in the RPDT depot with one of Lord Handelmort's packages during the Tribal Totem quest.
He is apparently a good friend of Sedridor as he says so each time a player talks to him; Merlin also mentions him as a friend and possesses knowledge of his teleporting people into stone, suggesting you seek his aid in freeing King Arthur from Morgan's spell.