Complex sentence: While inhabiting a body, Hive gains the host's memories while being able to manifest his monstrous appearance and can also devour humans with his parasites as a means of nourishment to make his host body highly durable and strong.
Split into simpler sentences: While inhabiting a body, Hive gains the host's memories, while also being able to manifest his monstrous true appearance. He can also devour humans with his parasites as a means of nourishment to make his host body durable and strong.