Can I create an event-based mbox? I don't see the 'Target' section in the event-based rules.

To create an event-based mbox, implement the mbox as a Dynamic Mbox in the custom code in the 'JavaScript / Third-Party Tags' section of the rule. In this implementation, mboxUpdate would be used instead of the built-in UI fields found in the 'Target' section of a page load rules. This option only appears when a Target tool is installed.  More info on Dynamic Mboxes here:https://marketing.adobe.com/resources/help/en_US/rec/r_Creating_a_Dynamic_Mbox.html

Once the condition of the rule is configured, navigate to the 'JavaScript / Third-Party Tags' section and add a script set to 'Non-Sequential JavaScript'. Set the script to 'Execute Globally'. (When the box for 'Execute Globally' is checked, it does not mean that it triggers on every page. Instead, it refers to the JavaScript scope of the tag.)

Then, in the script editor, add in the mboxDefine/mboxUpdate code. For example: