ScatterSpoke Retrospectives is the best retrospective tool for Agile Coaches, Scrum Masters, Engineers, and project managers. ScatterSpoke Retrospectives gives deep insight into your team health, output, and improvement opportunities.
Where does the content originate? on Retrospective Techniques for Coaches, Scrum Masters, and Other Facilitators | Trello
This Trello board is a great visual catalog and this card talks about some of the sources for the different activities. Close the card to see the Trello board.
Getting Value out of Agile Retrospectives | Ben Linders
Getting Value out of Agile Retrospectives: The book with many exercises for facilitating valuable agile retrospectives, supported with the why, what and how