Being in a stack formation imparts some duties and responsibilities for each member in the stack line.
The Direwolves utilize something called a Dynamic Stack. This means that individual players do not get assigned a stack position. Instead, team members are required to self-assemble into stacks where the roles and responsibilities are tied to the Position within the Stack, not to an individual person. This means that the position you are in the stack determines what you need to do, not who you are that determines what you need to do.
Each position within the stack formation has a role to play in order for a team stack to be successful. The first person in the stack is considered the team lead for the current technique, action or movement. If, due to circumstance, the stack order changes the first person in the stack is now calling out the next movement, technique or action.