Mist

Description

The formula processing of a Quickening, Concurrence and Esper-Ultimate works slightly differently than with other actions.

Since an action's event animation is played after its formula is applied, it's important that both the caster and target are not yet effected by its changes. Otherwise it can cause issues in certain scenarios (e.g. if target is KO'd).

Therefore, these actions won't affect their caster and target immediately. Instead, all changes are first internally merged and then applied to both characters after all event animations are finished.

As a result, it's impossible to determine to which extent the caster and target have already been affected during a Quickening or Concurrence.

Example

Vaan, Balthier and Ashe are in the active party and in a battle with Wolf A and Wolf B. Vaan casts Red Spiral on Wolf A. Afterwards, Balthier continues the chain with Fires of War, followed by Ashe with Intercession. Finally, the Quickening chain ends which triggers the Concurrence Inferno.

Order	Middleware	Caster	Target	Action
1	On Cast	Vaan	Wolf A	Red Spiral
2	On Hit	Vaan	Wolf A	Red Spiral
3	On Cast	Balthier	Wolf A	Fires of War
4	On Hit	Balthier	Wolf A	Fires of War
5	On Cast	Ashe	Wolf A	Intercession
6	On Hit	Ashe	Wolf A	Intercession
7	On Cast	Ashe	Wolf A	Inferno
8	On Cast	Ashe	Wolf B	Inferno
9	On Hit	Ashe	Wolf A	Inferno
10	On Hit	Ashe	Wolf B	Inferno
11	On Mist End	Vaan	Vaan	Red Spiral
12	On Mist End	Vaan	Wolf A	Red Spiral
13	On Mist End	Vaan	Balthier	Fires of War
14	On Mist End	Vaan	Ashe	Intercession
15	On Mist End	Vaan	Wolf B	Inferno

After OnHit middleware functions are executed for each caster and target, their changes are internally merged and then preserved. Once the Quickening chain ends, the changes are applied via OnMistEnd middleware functions.

Merge Operations

Each property uses one of 3 operations (Add, Or, Mov) when it's merged. Based on the property, it might be preferable to either overwrite the last actions' changes or only add to them.

Assume a Quickening reduces the target's HP by 100 and randomly either applies the status effect Slow or Blind, with a duration based on the caster's vitality.

If the Quickening is executed twice, the properties would be merged as follows:

Property	Operation	Initial	Last	Result
Removed HP	Add	100	100	200
Status Effect State	Or	0	1	1
Status Effect Duration	Mov	100	120	120

The removedHp property uses the merge operation Add. So the new value is being added on top of the currently preserved value. That way, the target's hp can be reduced by more than just 100.

The addedStatusEffects property uses the merge operation Or. So the new value overwrites the currently preserved value, but only if the latter is 0. That way, all of the target's status effects can be modified at once, but an action can also never remove the added status effects of the actions executed before it.

The addedStatusEffectDurations property uses the merge operation Mov. So the new value always overwrites the currently preserved value. That way, the formula's intent is not only preserved, but there is also an incentive to smartly chain Quickenings.

For a list of which properties use which merge operation, you can check out the mod spreadsheet in Resources.

Notes

The formula's outcome type is always set to 0 (successful) before processing functions of a middleware group. In theory, a mist action can have a different outcome type at the end, but the result will not be reflected by the game. For example, if the action misses, no "miss" text will be shown.

The caster of a Concurrence is the last caster of a Quickening.

The caster of all OnMistEnd functions is the caster of the initial Quickening. The same applies to the action.

In theory, a caster's and target's properties can still be modified before OnMistEnd middleware functions. Therefore, it's important to check the formula cause type (3 -> Mist) and skip those functions if necessary, similar to how it's done with function 320, for example.

While using the Mov Operation for some properties may seem bad at first, it's necessary to do so as otherwise the formula's intent would be automated.

Assume the target's hp is set to 100 twice using the matchedHp property.

If the merge operation Add is used, then the target's HP would be set to 200 which could be completely against the formula's intent as there is no way to know beforehand if it was meant to be beneficial or detrimental. The same goes for using the Mov operation when the new value is higher or lower than the currently preserved one.

However, if the new value always overwrites the current one, then the formula's intent is directly inherited. So even if an action can possibly worsen the changes applied by previously executed actions, it can also improve them and, most importantly, preserve the formula's intent.