These provide 40% increased maximum life to minions of their owner, which can stack with multiple spectres.
They have a basic attack.
They also trigger caustic ground when hit which deals okay chaos damage but is on a 4 second cooldown.
They also have a really high health pool, about 50% more compared to a Primal Crushclaw.
Overall, decent spectre for the buff, and could be interesting for builds that want to utilize things like Aukuna's will gloves.
These can be bought from the Breaker of Oaths as a corpse in the Affliction league mechanic.
This video was recorded in patch 3.23.