Kate Stone, currently known as Pink Silver (who comes under a surprising number of unusual aliases on IRC and elsewhere, changing between them nearly constantly for reasons known only to herself), is a mapper and modder that has come into the community primarily through the discovery of the ZDoom source port in the end of 2002. Ever since, she's been a frequent forum user there, and has programmed a few contributions to the port, the most prominent of these is A_LookEx, a modification to the sight check code that allows customized behavior for monsters like maximum and minimum sight distances, a maximum hearing distance, a custom alert state, and the ability to make monsters blind or completely deaf (not to be confused with the AMBUSH level flag behavior, which is different).