Complex sentence: Additionally, a "Realm of Reason" appeared in the 3rd edition, Reason was associated with scepticism and scholarship, and its "rational" aura alleviated the effects of the other four realms.
Split into simpler sentences: Additionally, a "Realm of Reason" appeared in the 3rd edition. "Reason" was associated with scepticism and scholarship, and its "rational" aura alleviated the effects of the other four realms.