This is the boss idea I'm thinking of:
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[img=http://img0.joyreactor.cc/pics/post/full/Great-Grey-Wolf-Sif-DS-%D0%BF%D0%B5%D1%80%D1%81%D0%BE%D0%BD%D0%B0%D0%B6%D0%B8-Dark-Souls-%D1%84%D1%8D%D0%BD%D0%B4%D0%BE%D0%BC%D1%8B-1051195.jpeg]

Basically it's Sif but in death he was tainted by the abyss and thus cursed to wander, with an unsatisfiable hunger to consume the souls of the curse to try and end it's pain but it can never do so. Two swords stick from it's body, showing what the poor beast went through in life to defend his master's grave (as a test for the Covenant of Artorias ring to traverse the abyss but that lore would be nonexistent in this world now). Part of the tail is rotted away and the lower jaw hangs loosely with an elongated tongue. I think it looks awesome and would be fun to fight.
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