How to see opposite team's ghost(spirit)?

[Cargalia]

was always under the impresson that you couldn't under no circumstances be able to view the opposite team's spirit. is this true ?

in badlands I was being targeted and followed around by an undead(can't remember class) he was around my level.

[Keftenk]

I think it's some strange random bug, but I have noticed with the phasing its popping up more and more often.

[Iltháes]

I believe there's a goblin in gadgetzan that gives you an item that allows you to see the enemy's spirit.

Or perhaps it's just an engineering/class ability that undead was using.

[Cargalia]

yes I was going to mention it being a phase bug, as just after posting this I saw a 58 tauren druid.

this was badlands, which I notice to have lots of phasing zones. so I believe this is a relevant theory

[Lotias]

Yeah its a bug! sometimes in BG's Ive seen ghosts running around or standing by enemy graveyards!