Aside from the broken masks, another quality that differentiates some arrancar from normal hollows would be the position of their hollow holes.
While the hole is normally located at the center of their chest, both as a symbol of the loss of their heart and because that is where the (saketsu) chain of destiny is attached, arrancar often have displaced hollow holes for some reason.
To normal souls that location is where it's chain of destiny ties it to it's body, or where the chain is free floating.
To a hollow, that is where it's hollow hole is located.
It also serves a purpose for shinigami, as seen when when Ichigo was stabbed through his chest and abdoman (in an attempt to remove his shinigami powers):
and when Ishida shot someone for the same reason:
Since these two locations are apparently the cores of a shinigami soul, it follows that arrancar should have a similar construction, and from what Ishida did and said, it appears that they do:
This is second time that we see Ishida attempt to cripple someone in this manner, and clearly the difference is that this time he only aimed for the center of the chest. An obvious explanation for this (assuming that any arrow can pierce her flesh once she's incapacitated) would be that her hollow hole is at the center of her abdoman and additional shots are unnecessary.
This would suggest that arrancar sometimes have displaced holes to accommodate their shinihami powers, while it's too early to really conclude anything besides that, it may be possible to gauge how powerful an arrancar is by looking at where their hollow holes are located (I would guess that the best configuration would be at a location that is neither at the center of the chest, nor in the middle of the abdoman).
Any other ideas about this?
Ideas? Other than that you're over-analyzing things for no reason, not really.
The holes are probably positioned simply as a way of differing the appearance of one arrancar from another. That Ishida can detect their soul links isn't remarkable, since he's a Quincy and can apparently detect tiny variations in spiritrons he should be able to see where their power is centered at easily enough. Their hollow holes need not match with the locations of their soul links for that.
I remember someone claimed once on DC++ (does anyone still use that?) that the hollow holes might reflect how the people had died. Then I pointed out that by that theory Ulquiorra is apparently a throat cancer victim, and then nicknamed him "Tracheotomy-boy". So we know it doesn't mean that. That brings up the interesting question of how exactly Tracheotomy-boy can talk though, since he has no vocal chords.
You say that as if it's a bad thing...
Originally Posted by erachima
And there's no reason for it serve as a means of differentiating them if over half of the time, their clothing covers up the hole.
And Ishida definitely did not choose to shoot where he did because of his ability to sense reishi, he specifically said that he shot there because it's where the powers of a shinigami are located, and that arrancar should have a similar physiology. Which brings up the question of why he didn't also shoot her in the abdoman (as he did in the past to another shinigami and as Byakuya did to Ichigo).
The vocal cord things is heavily debated in Naruto too (when Hidan was decapitated), I guess that we'll never know how people missing the correct organs somehow can still move air over their (nonexistent) vocal cords.
because he's a spirit?
it's the same reason why grimjaww can do a throaty laugh even though he has no stomach :P
Could be that the placements of the holes could signify the rank and power?
Why on earth would they possibly do that? The tats already fulfill that role, and there's been no noticeable trend in where they are.
There does seem to be some correspondence between the strength of an arrancar and how inhuman they are when transformed, but that's pretty normal for shonen series: the strong enemies are tough guys, the REALLY strong enemies are monsters, and the REALLY REALLY strong enemies are bishies and little kids.
^ Which is why I have high hopes for Wonderweiss.
You don't even think that there's any reason for the movement of the holes though? I'm not saying that any usable data can be gleaned from examining where they are at this point, I just think that there's more to it than just being a cosmetic effect.
Will Wonderweiss even be an opponent? And if so, who is going to be bastard enough to even be willing to fight him, let alone kill him? Ishida?
Tousen doesn't seem to be entirely convinced that he's exactly innocent, he's just "pure" apparently, maybe purely insane?
Besides, he has one of the best looking swords out of all the Espada, it'd be a waste not to use it.
His claymore's too out of proportion to his body for it to look good if he actually fought with it. Unless he has a sudden growth spurt, his battles will be either bare handed or released.