Talk:Corvo's Mask/@comment-187.37.173.163-20121022012153/@comment-92.237.233.226-20130112183707

If anyone payed any attention, Piero said the mask was designed to protect Corvo from the plague, and to hide his identity. The elixirs were probably helping as a second line of defence.

and before saying anything else, SPOILER ALERT! (read at own risk).

The Outsider is connected to the rats and for some odd reason, whales. But it was the Royal Spymaster (forgot his name) who brought the plague to the city and it spread due to the huge rat infestation, the plague transfered from the bites of infected rats, or due to extended contact to infected people, aka "Weepers".