Circle up.
Two people next to each other go in the circle.
The person to their left (before they entered circle) gives a topic.
Starting with the last person in, the two go back and forth giving examples of the topic.
(Example: Topic: Colors Person1: Blue Person 2: Green Person 3: Yellow)
All members of the circle pat their thighs while they are giving examples.
Whoever stumbles or repeats an examples is out.
Everyone shouts "thunderdome" when they get out.
Person who gave last topic is in.
Repeat.