In which order are aspects invoked when defending in Fate Accelerated?

Question

When a character takes one of the four actions and rolls the dice, they can decide to invoke aspects after seeing the total. For example, when chief engineer Yago Awain is trying to repair the broken witch-fuel reactors Carefully, and the task's difficulty is +4 (Great), he can decide to invoke his aspect One with the Machines to boost his roll to +4 or over when his unmodified roll is unsatisfactionary.

However, what if Yago is in a conflict, trying to wrestle an out-of-control service drone for instance? Let's say he Attacks the drone Forcefully, and the drone dodges to Defend Quickly. In which order do things happen? I see three options:

• Yago rolls and modifies his Attack action with aspect invokes first, after which the drone rolls and modifies its Defend action
• The drone rolls and modifies its Defend action with aspect invokes first, after which Yago rolls and modifies his Attack action
• Both parties roll, and are free to invoke aspects to modify their result afterwards until neither wants or is able to invoke any further aspects

Which is the correct one?

Answer 1

It's the third one. Both parties roll and see their totals. Then they can invoke aspects until neither can or wants to invoke any more, with no set order to who can invoke what when.

When you're following the steps in How To Do Stuff, both parties involved in the roll are moving through these steps together simultaneously. So when we reach this step:

Roll the dice, Add your bonus

Time to take up dice and roll. Take the bonus associated with the approach you’ve chosen and add it to the result on the dice. If you have a stunt that applies, add that too. That’s your total. Compare it to what your opponent (usually the GM) has.

... both parties have now made their roll, added their bonus, and see what the other party has. Only once both sides are done with this do we move on to the next step where they can invoke things:

Decide whether to modify the roll

Finally, decide whether you want to alter your roll by invoking aspects—this is discussed a lot in Aspects and Fate Points.

At this point players can use invocations and there's no set order here either: they can go back and forth, or one player could do multiple invocations in a row, etc. It's not over until they both decide they're not invoking anything else.

This does mean invoking can just continue back and forth with each player cancelling out the other's bonus or upping the ante, and that is OK. Sometimes players will be happy to spend resources to force the opponent to use up their own as well this way. Another time in a friend's Fate game, two players at opposing rolls realised they were both willing to spend all their respective fate points on the roll which would have gotten them both nowhere (the shifts difference still would've been about the same)—so they both agreed to spend none instead and let the roll resolve without invocations, which is also valid.

As a general principle for Fate Core/Accelerated: you always will know what you're up against numerically before having the choice to invoke — you're never invoking in the dark.

Answer 2

@doppelgreener's answer is correct in all particulars; no roll is final until both rolls are final. But while you can repeatedly volley Fate Points back and forth, often times you'll see a GM locking in a number for a player to hit in advance, not because they're getting the rules wrong but out of concern for pacing and flow. Here's why you as GM might want to do that, too.

1) Mook or Bad Guy?

In Fate Accelerated, lots of the opposition you fight can just be "mooks" - characters which roll overall at a specific quality, usually Mediocre (+0) or Average (+1), and which have "strengths" and "weaknesses" at +2/-2 from their roll. These don't have to correspond to player approaches, but can be generic things, like

Rampaging Service Drone -- Mediocre (+0) Mook
Aspects: Logic Virus Virus Logic, Sparks Everywhere
Good At: Moving Unpredictably (+2)
Bad At: Doing The Same Thing For Ten Seconds Straight (-2)

I'm assuming your giving the drone an approach to defend with was just for the sake of example, and it wasn't actually a fully-statted bad guy? Because the degree to which you dramatically struggle should correspond to how important in the plot something actually is. And mooks aren't that important.

2) One-Pass Opposition: Setting the Obstacle with Mooks

The language "set the obstacle" comes from Burning Wheel, but the principle is the same: as the GM, regardless of whether you're acting or defending, lock in your roll first to let your player know what they need to hit. This means you burn any Fate Points or free invokes you want, either to reroll or to pump the end value, before your player rolls.

Mostly this is for convenience: you're going to be running an awful lot of mooks, and every time you go back and forth you make the conflict longer. But it also fits the nature of mooks in that they can make a dramatic appearance, but they don't really take dramatic action.

But what if somebody lands a real corker of a hit that would clear the table of mooks and you still have points left in the scene pool? Don't spend them, even then. Let your player have a moment of glory in good luck or good planning.

3) Now I Have The Upper Hand: Dramatic Action with Bad Guys

It's important to remember that taking an action in a conflict doesn't mean taking a single discrete action - one punch, one shot, one lunge. So after the dice hit the table, you don't have to somehow work everything you spend Fate Points on into one continuous action.

And when both sets of dice hit the table and you're seesawing back and forth over how hard a hit is, or if it connects at all, you're narrating how the Fate Points (or free invokes) come into play every time. This can easily produce the kind of dramatic struggle back and forth that you want out of a confrontation with an actual full-character-sheet bad guy.