Mythic can generate JSON or XML style reports. If you need a PDF version, simply generate the XML, open it up locally, and then in your browser save it off to PDF.
Report generation is located from the checker flag icon from the top navigation bar.
You can select your output format, if you want to include MITRE ATT&CK mappings inline with each tasking and if you want a MITRE ATT&CK Summary at the end. You can also optionally exclude certain callbacks, usernames, and hostnames from being included in the generated report.
The final generated report can be downloaded from this screen when it's ready via a toast notification. If you navigate away before it's done though, the report is also always available from the "files" section of the search page (click the paper clip icon at the top and select "Uploads" instead of "Downloads").