I'm not an expert about MB so I can't say if the PCs should know in advance that a particular mask is resembling that specifical god. However, the omens are very evocative!
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Thank you! As to whether they would know? No, since MB doesn’t have Gods in the typical RPG sense at all, and every Myth operates under its own internal logic, and there need be no consistency from one to the next. Essentially, every Knight is as in the dark as a layperson NPC in nearly every Myth, they just have the fortitude & tools to resolve it.