When I attack a legend through a zone, is that legend considered to be a "unit" of attacker?

When I defend a zone with a legend (attached by BQ36 Descendant of Gods), is that legend considered to be a "unit" of defender?

Can I use AU42 Invoke Khaine’s Wrath to destroy the legend that participated in combat?

AU42 Invoke Khaine’s Wrath
Play at the end of any battlefield phase.
Action: Destroy all units that participated in combat this phase.

Thanks for Reply

No, no and no.

A legend is not a unit, and will not be affected by cards affecting units.

"During the battlefield phase, a legend may use its battlefield power to attack as though it were a unit located in the battlefield zone."

 “as though it were a unit” means it is not a unit in fact, and also can not count as a unit. However, you can just understand the effect of a legend in combat that is similar with a unit.

And also, "Legends are their own card type and are not affected by card effects that target unit, support, or tactic cards."

Legends can surely be affected by card effects, such as Promenade of Malice. It is just not affected by card effects that target unit, support, or tactic cards.