The mycause event dashboard has an email communication tool that allows for event managers to easily alter the wording of automated emails and create customised emails to send out to large groups of participants at once.
To send out a mass email to all fundraisers in the event dashboard click on 'Marketing'.
Then you will need to click on the 'Email communication' sub-tab, scroll down to where it states 'send customised emails'.
Before you send your message check you've ticked the box to send the message to 'All active fundraisers'.