TL;DR: Corpses that you don't create show up as consumable but are not unless you have a self-created corpse in the area, making it extremely difficult in combat to know which corpses you can and can't consume.

I reported this bug a while back with no word, and had hoped it would have been fixed in the last major update or incremental patch but it was not.

Currently, Necromancers (and possibly WWs + Templars) suffer from a bug where corpses that you did not create or damage will not be consumable unless there is also a corpse that you created/killed/damaged in the area. What do I mean by this?

Let's take the most common scenario. Pretend you port into IC or Cyrodiil and then roll up on your groupmates already fighting other players or mobs. There's already a healthy serving of corpses on the ground, highlighted blue and all, but you won't be able to consume them. Again, the corpses show up blue, indicating that they should be able to be consumed, but unless you throw down a Ghost/Armor/Blastbones corpse next to the already existing corpses, you will not be able to consume them.

This bug has gotten me killed numerous times, as when you're fighting in PvP and kiting around, you may kite towards a few corpses you see to throw down one of your corpse consumption heals, only to be disappointed and dead shortly after when you realize you can't actually consume said corpses.

@ZOS_Kevin This bug is really holding back Necro, despite not being immediately apparent in every scenario. It's been going on for so long I don't even remember what the intended behavior is, but corpses you don't create should either be consumable, or not marked as consumable. Currently, they are not consumable, but marked as consumable (again, unless you have a self-created corpse in the area).