Mana Strider

Mana striders are tall, alien machines known for abducting magic users and raiding trade caravans for magical items.

Their origins are mysterious, they have never been destroyed and nobody captured by one has ever returned.

Plans have been made to take them down but the military force needed wouldn't be able to navigate the area they are usually seen in.

But aside from that, they generally ignore anything magical as long as it stays well away, they will kill anything that gets close, and capture anything magical.