Comments made to our Salt & Sanctuary Wiki
The projectiles the ghosts shoot deal Arcane damage, not Holy.
If the Axe is thrown from very high, it can get stuck mid-air. It can also be dropped outside of the boss arena. This boss needs a patch.
Seems this boss has a ton of glitches associated with it, adding to that I first encountered this boss accidentally because I went to the Pitchwoods before Ruined Temple, so I came into the boss room from the left side (exit I guess) where there wasn't a candelabra until it was too late and I was being pounded by those projectiles. All other bosses with multiple entrance points have had candelabras on either side, pretty annoying losing my salt and time, or I would have horned out.
that is because that passage is not intended to be possible
Pitchwoods down to the bottom of Ruined Temple is intended and quite possible (it's also why Redshift Brand is the only intended optional brand, and why Spindlebeasts are hell itself), but I think they forgot to put in the candelabras with that path in mind. Both The Coveted and the Bloodless Prince lack candelabras on their left entrance (though both have a shrine/sanctuary nearby on that side with no enemies between the revival and the boss).
i m pretty sure blood prince has candelabras in only right side too
fun fact: if you get the one ghost to get stuck on one side of the map, and then go over to the other side of the map with the axeghost following you, and then stop attacking the axe and stop moving, the axe ghost stops too. and from this point, if you have poison knives, you can poison the axe from a distance and it'll take damage, but the ghost wont pick it up.
This was a really interesting idea for a boss, probably my favorite so far purely for its originality. Also, upon my second fight with these guys they seemed to just stop throwing lightning for some reason, the non axe wielded just floated around until the axe was dropped.
This boss can actually be skipped

if you die to axe you need to deal certain damage to get your salt back while if you die to arcane bolts it will be on an otherwordly creature inside boss.
Come in from the right. Stay close to the entrance and only aggro 1 ghost. Stay to the right of the arena and effortlessly kill this boss. Get reward. Walk to the left, other ghost insta dies. Duplicate reward.