Atlantis - Known Issues: General Feats, Artifacts, and Content Collections for Atlantis are still in progress and not yet completed. Base Items Atlantean Base Item boxes are being sold on the Titan’s Vendor instead of the Atlantean Vendor. 1 Player Atlantis: Royal Palace The final boss will become undefeatable if you are KO’d after getting him down to 75% health. 4 Player Atlantis: Silent School The event version of Atlantis: Silent School has been temporarily removed from the On-Duty event list.