Welcome to UO Cataclysm


Marketplaces reminiscent of a lost era..

The Frost Elf Den, a dangerous destination for an adventurer.

Custom crafting includes weapons, armor, potions and more!

Lively towns centered on a bustling economy.

Rare custom mounts can be tamed only by the brave.

Perilous journeys into our dungeons await.

Static houses are available for your RP pleasure.

PVP in our custom duel pits where you can risk it all!

Custom Mob Locations with Storylines Around the World.

UOCataclysm is a perfect blend of the best of Sphere 51a, T2A and what many of us consider the 'golden age' of Ultima Online. UOC has spared no expense to design a server which functions with all of the greatness of the original Sphere but powered by RunUO. Be apart of a rich, custom world with a unique flair and quality the most nostalgic can appreciate. Finally a server you can enjoy that lives up to its promises on being true to the original Sphere playstyle!

Cataclysm Expansion III Has been released 5/12/2018!



Town Crier

Expansion II Launches 12/18/2016 at 5:00PM PST (GMT -8:00)

The largest update of the year, worthy of the Expansion title! There's too many new features to list here, see the forums for the Patch Notes!

High End Platinum Rewards! Customized Item or Wearable!

We've added high end Platinum rewards to the Platinum Reward Stone in the Safe Zone! You can obtain Coupons to exchange for a new customized wearable item, or house decoration item of your liking! Remember, you can only obtain Platinum for being online in any area besides the Safe Zone! For specifics, please see the forums!

Super Sunday Events! 11/6/16

We will be having an old school staff hosted Super Sunday this weekend! Starting at 8:00 PM PST (GMT -8:00). We hope to see you all there! See the forums for details!

Patch 20 Deploys on Cataclysm!

It's a feature release on Cataclysm! We've added two new automated events, and have a few more fixes and features as well! See the news on the forums here: Patch 20 Notes

Expansion Client is now available!

We have a new client full of features, nostalgia, and expanded content! Players are required to either download the new installer, or update their existing client files! Please use the download links above, or see more information on the forums here: Client Update.



→ Download Installer ← (Required)
Server: login.cataclysmuo.com 
Port: 2593




Screenshot of the Moment


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