Debug logs are essential for troubleshooting and understanding the execution flow of a playbook in Splunk Phantom. The debug log for a playbook execution can be viewed by navigating to the Investigation page of a specific event or container. Within the Recent Activity panel, there is an action menu associated with each playbook run. Selecting "Debug Log" from this menu will display the detailed execution log, showing each action taken, the results of those actions, and any errors or messages generated during the playbook run.

Explanation
The Phantom App for Splunk allows a user to run Splunk queries from within Phantom. This app provides actions such as run query, ingest events, and save search, which enable the user to interact with Splunk from Phantom playbooks or the Phantom UI. The other apps are not relevant for this use case. The Splunk App for Phantom is used to send data from Splunk to Phantom. The Integrated Splunk/Phantom app is a deprecated app that was replaced by the Splunk App for Phantom. The Splunk App for Phantom Reporting is used to generate reports on Phantom activity from Splunk. Reference, page 1.

The Files tab on the Investigate page allows the user to upload, download, and view files related to an investigation. A user can upload the output from a detonate action to the Files tab for further investigation, such as analyzing the file metadata, content, or hash. Files tab items and artifacts are not the only data sources that can populate active cases, as cases can also include events, tasks, notes, and comments. Files tab items can be added to investigations by using the add file action block or the Add File button on the Files tab. Phantom memory requirements may increase depending on the Files tab usage, as files are stored in the Phantom database.
The Files tab on the Investigate page in Splunk Phantom is an area where users can manage and analyze files related to an investigation. Users can upload files, such as outputs from a 'detonate file' action which analyzes potentially malicious files in a sandbox environment. The files tab allows users to store and further investigate these outputs, which can include reports, logs, or any other file types that have been generated or are relevant to the investigation. The Files tab is an integral part of the investigation process, providing easy access to file data for analysis and correlation with other incident data.

Passing data between playbooks in Splunk Phantom is most efficiently done through action results. Playbooks are composed of actions, which are individual steps that perform operations. When an action is executed, it generates results, which can include data like IP addresses, usernames, or any other relevant information.
These results can be passed to subsequent playbooks as input, allowing for a seamless flow of information and enabling complex automation sequences. Other methods, like using the file system, artifacts, or KV Store, are less direct and can be more complex to implement for this purpose.