Wraithseer

The Wraithseer is an Eldar walker in the same family as the Wraithlord and the Wraithguard in that they're powered by the dead. However, whereas a Wraithlord would be powered by the soul stone of a dead Eldar warrior (Presumably an Aspect Warrior) and then shepherded by a Spiritseer, the Wraithseer cuts out the middleman and puts in a Spiritseer's soul stone as the pilot, allowing them to exert greater control over his wraithbone shell and the shells of others. In a way, they resemble the Blood Angels' Librarian Dreadnoughts, except they're not quite as ridiculous a premise. However, they're just as grand a rarity, as the secrets behind making these psychic machines is lost to the general populace. Also, despite the badass practicality, these titans are used more as a last-ditch resort, more so than using Wrath-constructs normally entail.

On the field, it is a legendary thing to field if your opponent lets you field Forge World (But it can't be used as a lone HQ, it has to be coupled with someone else, presumably a Spiritseer), with both incredible support for other Wraith-units and some incredible weapons like the D-cannon and the Brightlance to use.