Ancient purple robes

"Mundungus redeemed himself slightly in Mrs. Weasley’s eyes by rescuing Ron from an ancient set of purple robes that had tried to strangle him when he removed them from their wardrobe."

- Mundungus Fletcher saving Ronald Weasley from these robes

An Ancient set of purple robes were dark artefacts that were bewitched to strangle anyone who came into close contact with them.

History
The pure-blood House of Black came into possession of these robes, and kept them in a wardrobe in an upstairs bedroom at 12 Grimmauld Place, their family home. In August 1995, whilst renovating the house along with the Order of the Phoenix, Ronald Weasley encountered these robes when he tried to remove them from a wardrobe, only for them to attack him. Thankfully, Mundungus Fletcher managed to rescue Ron from being strangled by these robes, for which Ron's mother Molly Weasley thanked him for somewhat.