The worlds are saved in your browser's neighborhood storage, you may export them as EPK data files and import them all over again on all other Eaglercraft websites that also help singleplayer. To ban users by common expression, use: eag-ban-regex with a regular expression to match the username in https://www.reddit.com/user/ukIsmine/comments/11suiwb/a_comprehensive_guide_to_eaglercraft_minecraft/