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

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.

Running Strong for a Month!

Can you believe that Cataclysm UO is now a month old? It seems like it was just yesterday we had 5 players on, a couple of server crash issues, no chatting system, taming much too difficult, etc. A lot has changed in that month, just take a look at our Patch Notes in the forums! We've now peaked at over 40 users according to UOPortal and JoinUO! It seems we have been averaging 25-35 players depending on the time of day. We're in a good place for such a young shard, and have much room to grow! I encourage all of you to continue voting and spreading the word!

Lag Issue Fixed & New Forums

We have migrated to a new host today which is more centrally located for all players on the server (now in Dallas, TX). Pings are good and best of all, the lag we were experiencing is gone! The issue with UOPortal not finding our online player count was resolved with this migration as well. I know we also had issues with our old forums, so I've gone ahead and ripped the old one out and implemented a much better solution that works. As always, please let us know if you run into any issues or have any suggestions.

We are Live! Cataclysm UO Has Officialy Launched!

Cataclysm Ultima Online Grand Opening!

We would like to thank everyone for visiting the community on launch day! We will be available for any questions and comments regarding the shard today! Please join us in a brand new world!

Picking up the Torch: Cataclysm UO Official Launch on 12/13/14

We are proud to announce that we are ready for launch this weekend on Saturday, December 13th 2014 at 7:00AM Pacific Standard Time (GMT -8:00).



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




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