Fate Core
The Exchange
Exchanges in a conflict are a little more complicated than in contests. In an exchange, every character gets a turn to take an action. GMs, you get to go once for every NPC you control in the conflict.
Most of the time, you’re going to be attacking another character or creating an advantage on your turn, because that’s the point of a conflict—take your opponent out, or set things up to make it easier to take your opponent out.
GMs, if you have a lot of nameless NPCs in your scene, feel free to have them use passive opposition to keep your dice rolling down. Also, consider using mobs instead of individual NPCs to keep things simple.
However, if you have a secondary objective in the conflict scene, you might need to roll an overcome action instead. You’ll encounter this most often if you want to move between zones but there’s a situation aspect in place making that problematic.
Regardless, you only get to make one skill roll on your turn in an exchange, unless you’re defending against someone else’s action—you can do that as many times as you want. You can even make defend actions on behalf of others, so long as you fulfill two conditions: it has to be reasonable for you to interpose yourself between the attack and its target, and you have to suffer the effects of any failed rolls.
Full Defense
If you want, you can forgo your action for the exchange to concentrate on defense. You don’t get to do anything proactive, but you do get to roll all defend actions for the exchange at a +2 bonus.
In the first exchange of our warehouse fight, Cynere goes first. Lily has Cynere attack the thug that’s eyeing her. That’s her action for the exchange—she can still roll to defend whenever she needs to, but she can’t do anything else proactive until her next turn.
On Ryan’s turn, he has Zird do a full defense—normally, he’d be able to defend and get an action this exchange, but instead, he gets a +2 to his defense rolls until his next turn.
On Lenny’s turn, he has Landon create an advantage by placing an aspect on Og called Hemmed In, hoping to corner him between some crates. That’s his action for the exchange.
Amanda goes last, and she just has all of her NPCs attack their chosen targets.