The ring event that came with Chaos

You need to get a level 40+ character to level 40 times, so you can still get it on other adventurers. As for the items, I don't believe they are nerfed. Don't forget, adventurer rings aren't the only items. You can get earrings (Cygnus), a mask (Dual Blade), Lilin's Ring (Aran), Dragon Glasses (Evan), and the Resistance Ring (Resistance). All items have weapon attack, can be worn by any class, and can be transferred through account (at least one time). There's a thread around the forums somewhere.