UPDATE: I found that the runes can only be sacrificed if all copies are removed from all (non-walkthrough) battlegroups While I understand that the runes obtained in walkthrough decks are supposed to be untradable and unforgable, they are also preventing me from sacrificing non-champion runes or the same name. For example, I got the "Demon Prince" deck, and wanted to sacrifice my extra Mark of Sheoul, but was unable to do so.
I did remove them all by setting up a trader for the warbanners, then cancel the trade and i could sacrifice all the extra warbanners and just keep the ones that was given out for free with the 8 walkthroughs.
Simple. You had a pre-existing Mark of Sheoul that was being used by one or more decks, and you received a new MoS being used by the free BG. New MoS would be un-shard-able even if you remove it from all BGs, but your previous MoS can be Sacrificed once you remove it from all BGs that are using it. That is true for any shard-able rune. The new runes aren't preventing you from sacrificing your previously owned runes, BUT, there presence is ambiguous in the collection making it difficult to determine what can be sacrificed and what can not. Ideally, the Forge should show the BGs a given rune is occupying. It would also be hugely useful to be able to remove a rune from a BG while you are in Forge. Having to go to Trader to see where the runes are being used, then to Deck Manager to remove them, then to Forge to sacrifice them is quite a pain. Furthermore, the free runes should be distinguished in some fashion, making it clear that removing it from a BG won't free it to be sacrificed. I too went through this last night; not fun.
Ummm, is that the Arrowsinger you received as part of the free battle group, Rapid Assault? I'll bet it is, especially as you only have 1. You can't Sacrifice runes from the free battle groups.
Same thing happening here except mine is a sundered warbanner. I can't sacrifice it in either the rune forge or the client. I have already removed all copies of the rune from all batlegroups, so that's not the issue. For some reason, these extra copies are being flagged as not fully owned when I win them. I'm pretty sure this has happened with other runes I have won as well.
If it's from the sundered battle group you get from the walkthrough it's unsacrificeable. Can't sacrifice those free BG runes.
I understand that the free copy is not owned and is thus unsacrificable. However, the two other copies I've earned should be sacrificable and they are (with a little fiddling of the forge interface). The forge will not let me cycle through different copies of that rune and always attempts to sacrificed the unowned copy of the rune, returning an error. I have since figured it out though. Set all your decks with copies of this rune to the very last rune in the stack (for mine, it was the third copy). Then the forge should allow you to sacrifice the other copies.
I was able to sacrifice ALL of my iron first banners....even tho one came from a BG!! I also have 3 sundered lands banners, but cant break any of them or my provencial markers OR my tribal post!