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

Support Your Shard, Support Yourself in June on CataclysmUO!

With Patch 15 around the corner, our new marketing campaign is in full swing and has lots of rewards for players who participate! Idling your characters, up voting our reddit post, and a YouTube video contest is encouraged! We are grateful for such wonderful players and thankful for your support! See more details about this campaign and how you can participate here.

Patch 14 is live

The new armor recipes are active! Rare Dye Tubs have been reworked. One dye tub is allowed per account (therefore 2 per person, because everyone may have 2 accounts), and every GM Tailor will be allowed to choose their GM reward tub/color again. Choose wisely! There are many more key updates - Read the full changelog here.

Patch 12 Deploys on CUO

Were proud to announce Patch 12! This maintenance patch polishes many of the features introduced in Patch 11 such as new power hour and PvP updates. It also introduces some needed fixes. New tweaks to weapons will further balance PvP and continue to perfect era accuracy. You can read the details of the new changes here.

Patch 11 Deploys on Cataclysm!

It's been busy on the development side here at CUO! We're deploying our biggest patch yet, you can see the changes here. This all-inclusive update deploys many new changes to all aspects of the game: PvP, PvM, Crafting, etc. New era accurate changes polish the PvP system, making it more dynamic and authentic. Added many new crafting items to Carpentry and Tailoring, and new custom Tailoring armors. Power hour has also been added, and much more!

Patch 8 Live!

Hello all, I'm pleased to announce that we've now published Patch 8. With this patch comes various fixes to the vulnerabilities of PKing players within houses, public moongates working a lot better, working guild doors, players losing fame when they die and much much more. For the full details please read this post: Patch 8.



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Server: login.cataclysmuo.com 
Port: 2593




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