Marketo's Munchkin API is available as an alternative Sync Lead process, useful when dealing with large scale activity tracking. 

In order to push data to Marketo, a Marketo Bridge must be created and the Marketo Settings     configured. For more information, refer to the Marketo Bridge chapter in this manual.

The Munchkin API can be configured in the Munchkin API Settings section of the Marketo Bridge. A trusted email source must be identified in these settings, for example, %globals_user_attribute_email%.

Once you have finished configuring the settings of the Munchkin API, you can use the  global keyword %globals_marketo_munchkin_init:X% to print the initialisation code for the Munchkin API call, where X is the asset ID of the Marketo Bridge.

Please note that the Munchkin API requires an Email attribute to be specified for every Associate Lead call; this email address will be used to generate a hash to pass along with the API call. As a result, a Munchkin Email Source must be configured in the Munchkin API Settings section of the Marketo Bridge.

The Munchkin API has no daily request limit, unlike the Sync Lead API which has a request limit of 10,000. This means that it is ideal for large scale sites with greater tracking needs. However, unlike the Sync Lead API, the Munchkin API doesn't immediately update the lead data in the Marketo database; this could take up to a day after the request is made.

Due to both these strengths and limitations, it is advised that Squiz Matrix's Sync Lead API and Marketo Sync Lead submission action be used when dealing with personal sites with smaller tracking requirements. However, if frequent lead syncs and greater user activity tracking is necessary, the Munchkin API may be better suited for your needs.