If d2 is slowly bringing back d1 weapons which according to Bungie were all destroyed by mayor mccheese then surely touch of malice would fit in with current lore and connect to savathun since a piece of oryx's soul is trapped inside it. Edit: I'm not referring to the abilities of the weapon I'm speaking from a lore sense. Edit 2: I've just has a super cool idea. We know Eris is off fingering the hive, let's assume she took ToM with her. She gets killed by Savathun and leaves ToM behind. We have to somehow take an essence from Oryx's dead body (still floating around Saturn) and combine with his soul inside the ToM and it makes a super awesome weapon used to kill Savathun.