Everybody sums up the last iteration in 3 words Source:
Ask everyone to describe the last iteration with just 3 words. Give them a minute to come up with something, then go around the team. This helps people recall the last iteration so that they have some ground to start from.
Draw a speedboat onto a flip chart paper. Give it a strong motor as well as a heavy anchor. Team members silently write on sticky notes what propelled the team forward and what kept it in place. One idea per note. Post the stickies motor and anchor respectively. Read out each one and discuss how you can increase 'motors' and cut 'anchors'.
Variation: Some people add an iceberg in the back of the image. The iceberg represents obstacles they already see coming.
If your team has a tendency to see obstacles outside of their team and influence and primarily wants others to change, you can try this activity:
Draw a big rectangle on the board and another rectangle inside of it, like a picture frame. Hang all complaints and grievances that surfaced in previous phases into the frame.
Now comes the interesting twist: Explain that if they want anything in the outside frame to change, they will have to do something themselves to affect that change. Ask the team to come up with actions they can do. Put these actions into the inner rectangle (near the outer sticky they are addressing).
Let team members appreciate each other and end positively Source:
Agile Retrospectives who took it from 'The Satir Model: Family Therapy and Beyond'
Start by giving a sincere appreciation of one of the participants. It can be anything they contributed: help to the team or you, a solved problem, ...Then invite others and wait for someone to work up the nerve. Close, when no one has talked for a minute.