What a campaign is
A campaign is what a HubSpot workflow talks to. It holds one or more pools (in order), the sender and branding to use, and the switch that lets it send.
Enabled
A campaign with Enabled off answers every workflow with blocked, campaign disabled. Nothing is lost; the contact stays in the workflow and HubSpot retries. Turn it on when the pools are ready.
The workflow side
In HubSpot, add the mxAURA: Send next message action to a workflow and pick the campaign. Every time a contact reaches that step, mxAURA picks their next message and HubSpot sends it. Re-enroll to send the next one; most people use a delay + re-enroll loop.
Event. Pick the event a campaign is built around in the toolbar. Rows that serve a phase of the event (seeding, event, follow-up) are scheduled rows on its dates and show the phase as their type.