: Or... Maybe he just doesn't have a face... Hmm?
Nah. We've already got Soulblighter like that, and besides that's rather boring. Having him have no true form is better.
Also, to conserve posts, I'll post my further ideas here:
The party hunting down the Faceless Man is lead by the journal writer, a journeyman, who is the brother of Nine Eagle whatshisface, the guy that killed the Deceiver. He expects to rendezvous with his brothers forces returning from Seven Gates after killing the Deceiver, so that the two of them can hunt down the Faceless Man together. The Lurker has meanwhile been killed elsewhere.
Someone asks why do the Fallen keep attacking after Balor died. Well, they're evil, duh. Myrdred kept attacking, I'm sure Shiver and The Watcher would have as well, etc. Besides that, for whatever reason they did, they did, because we know they were killed in the years following Balor's death, which they wouldn't have been had they disappeared like Soulblighter.
The artifact used by Whatshisface against the Faceless Man was forged ages ago by a dark archmage for use against the Faceless Man, back when he was an avatara.