First off, I think I should make it plainly clear that the location of the brand isn't necessarily significant and there is no reason as to why it should be. We have no evidence that it is and therefore, all of the following is pure speculation...
In Volume 10, Episode 53, we're introduced to Gaiseric by Charlotte during the mission to rescue Griffith. We're also given a hint as to what the time period in which Gaeseric lived was like. Charlotte claims that, "In those days [the] continent saw constant warring between small city-states and many different tribes. Apparently it was an age of rival warlords. Continuous warfare ruined the land, and due to food shortages, plague and the like... it's said that fully a third of the population died."
Judeau adds that, "But God finally decided he couldn't condone the Skull King's deeds and sent five angels. By lightning and great earthquakes, the city was erased from the face of the Earth without a trace in the span of a night."
Five pages later, we see the floor of the Tower of Rebirth which shows the brand of sacrifice embedded into the foreheads of ancient corpses. Now, of course this could have just simply been the most effective way to show that these people had been branded prior to death, yet, while definitely a reasonable explanation for the brand location, I doubt that is the case.
In Volume 12, Episode 78, Griffith willingly sacrifices the Band of the Falcon during the Eclipse Ceremony and, as a result, Void unleashes the brand onto the band members. We're shown nine unknown members become branded and then, we see Casca, Corkus, Pippin, Judeau, and Guts become branded. Each of those five receives the brand on a different part of their body. Casca is branded on the chest, Corkus on the forehead, Pippin on the arm, Judeau on the hand, and Guts on the neck. Strangely enough, it appears as though the nine unknown members all receive the brand on the same part of their bodies; somewhere around the chest.
Obviously it has never been confirmed, however, it seems to me, pretty likely that Miura chose to place the brand on those specific and different parts of the main characters' bodies for a reason. Story-wise, I doubt this different placement was somehow intentionally done by Void or Griffith, so, one might assume that there there is some sort of deeper meaning as to why the brand of sacrifice takes to different parts of the body.
Let's focus on Corkus and the ancient corpses at the bottom of the Tower of Rebirth. Both Corkus and the corpses are branded on the forehead. In fact, from what we can tell, every corpse we can clearly see at the bottom of the tower has been branded on the forehead. Why? If we accept the notion that location of the brand is important, then we can infer that these sacrifices were people who had something fundamental in common. I don't want to assume too much, but, if we want to get a little more speculative, perhaps the brand being only on the foreheads of Corkus and the ancient corpses was due to them sharing some sort of common belief or more likely, because they shared a similar way of thinking.
If this is indeed the case, it makes the events of Gaiseric's time all the more mysterious. Perhaps we'll be given further insight on the brand, the Godhand, and the IoE after the gang arrives in Elfhelm and is introduced to a certain elf king. Of course, all of this is highly speculative. Nevertheless, I'm curious as to what your guys' thoughts are on the matter.
In Volume 10, Episode 53, we're introduced to Gaiseric by Charlotte during the mission to rescue Griffith. We're also given a hint as to what the time period in which Gaeseric lived was like. Charlotte claims that, "In those days [the] continent saw constant warring between small city-states and many different tribes. Apparently it was an age of rival warlords. Continuous warfare ruined the land, and due to food shortages, plague and the like... it's said that fully a third of the population died."
Judeau adds that, "But God finally decided he couldn't condone the Skull King's deeds and sent five angels. By lightning and great earthquakes, the city was erased from the face of the Earth without a trace in the span of a night."
Five pages later, we see the floor of the Tower of Rebirth which shows the brand of sacrifice embedded into the foreheads of ancient corpses. Now, of course this could have just simply been the most effective way to show that these people had been branded prior to death, yet, while definitely a reasonable explanation for the brand location, I doubt that is the case.
In Volume 12, Episode 78, Griffith willingly sacrifices the Band of the Falcon during the Eclipse Ceremony and, as a result, Void unleashes the brand onto the band members. We're shown nine unknown members become branded and then, we see Casca, Corkus, Pippin, Judeau, and Guts become branded. Each of those five receives the brand on a different part of their body. Casca is branded on the chest, Corkus on the forehead, Pippin on the arm, Judeau on the hand, and Guts on the neck. Strangely enough, it appears as though the nine unknown members all receive the brand on the same part of their bodies; somewhere around the chest.
Obviously it has never been confirmed, however, it seems to me, pretty likely that Miura chose to place the brand on those specific and different parts of the main characters' bodies for a reason. Story-wise, I doubt this different placement was somehow intentionally done by Void or Griffith, so, one might assume that there there is some sort of deeper meaning as to why the brand of sacrifice takes to different parts of the body.
Let's focus on Corkus and the ancient corpses at the bottom of the Tower of Rebirth. Both Corkus and the corpses are branded on the forehead. In fact, from what we can tell, every corpse we can clearly see at the bottom of the tower has been branded on the forehead. Why? If we accept the notion that location of the brand is important, then we can infer that these sacrifices were people who had something fundamental in common. I don't want to assume too much, but, if we want to get a little more speculative, perhaps the brand being only on the foreheads of Corkus and the ancient corpses was due to them sharing some sort of common belief or more likely, because they shared a similar way of thinking.
If this is indeed the case, it makes the events of Gaiseric's time all the more mysterious. Perhaps we'll be given further insight on the brand, the Godhand, and the IoE after the gang arrives in Elfhelm and is introduced to a certain elf king. Of course, all of this is highly speculative. Nevertheless, I'm curious as to what your guys' thoughts are on the matter.