User blog comment:Hyperborean/"The House of Hades" – official expectations blog/@comment-10750309-20130902134255

We know that Frank's life depends on a piece of firewood. And if that firewood burns, he'll die, right? Can Frank be also killed by weapons? Well if he can't, then he's immortal if the piece of firewood will not be consumed. This is unlikely.

What I'm thinking is that if Frank is about to die, then the piece of firewood automatically ignites. Iris hinted that Frank will see the flame in the firewood as he is about to die.

I'm having this scene in mind that Frank is lying on the ground battle wounded and about to die. He sacrificed himself just so the others will survive. The firewood ignites automatically and he bids farewell to everyone and says some things about them. And as he sees the events that happened in his life, he'll realizes some things and just stares at the fire until the fire dies. Creepy.