D&D Beyond offers the ability to link certain aspects on the forum in mouse-over triggered tooltips, such as magic items, monsters or combat actions - examples being Adult Black Dragon and dash. To create tooltips in this way as these, use the appropriate [tag][/tag] around the desired subject.
These tooltips can be used in most text boxes on D&D Beyond, such as: forum posts; campaign notes section; homebrew descriptions.
Example: [magicitem]Sun Blade[/ magicitem] (Without spaces within the [ ] brackets.)
Use the following within the [ ][/ ] bracket system: