I used the Search Feature, but only found vague references that didn't answer my question so I apologize if this has been asked before.
I know it costs me 20 to form one and 5 to join, my question is:
How much stamina does it cost me to initiate a group attak, and how much (if any) does it cost the people in the group.
Thank you in advance for answering my noob question
There is no further stam cost than the ones you listed in your post.

