This is Neil Armstrong in person, he's raised from death by the White Walkers. Unlike all the other wights, he is special to them as he was the first human to walk on the surface of the moon, so they decide to call him "The moon walker". He was 39 years old when he stepped onto the moon, but as he forgot a lot about his first life, he thinks he was 32 years old and that's why he added the number "32" to his username