Combat Mechanics (Sky)

This page explains the basic mechanics of combat in Trails in the Sky FC, SC, and the 3rd.

Entering Combat

When the party makes contact with an enemy in the overworld, the game changes to the battle field (a 17x17 grid made of squares) and combat is entered. Depending on the way contact is made, the battle can start normally, with a preemptive strike on the party's side (if the party contacted the enemy from the back), or ambushed by the enemy (if the enemy contacted the party from the back). Combat can also be entered from a scene, from extermination confirmations or from opening a chest, which save exceptions start battles without advantages on either side.

Normal battles start with the enemy on one end of the field and the party in the other, according to the formation set in the Tactics menu. Each unit will have a random delay until their first turn comes (explained later). The party's random delay will be skewed according to the party walking order, so that the members at the front will tend to have lower delay than the members at the back.

Preemptive Strike

If combat is entered through contacting an enemy from their back, the battle will start with a preemptive strike: the enemy will have a much larger delay until their first turn, allowing for more party turns before they're able to act. Otherwise the battle will proceed as normal.

Ambush

If combat is entered through the enemy contacting a party member's back, the battle will start as an enemy ambush: formations for both enemy and party will be ignored, and the enemies will surround the party members in a circle on the field. The party members will have a large delay before their first turn, which will likely allow the enemy to act before any of the party members. Otherwise the battle will proceed as normal.

Delay and Speed

The Action Time Battle system determines the order in which the units will take turns. For this, the game uses AT Units (AT for short) as a measure of the time it takes for a unit to have their next turn. Every action has a different Base Delay associated with them in AT units:

• Moving (or not being able to act due to status effects) has a base delay of 20 AT.
• Regular attacks have a base delay of 30 AT.
• Using an item has a base delay of 20 AT.
• Crafts each have a different base delay, expressed in the tables.
• Arts have two base delays: the Cast delay before the art takes effect, and the Delay after casting before the caster can act again. Cast quartz will reduce only the former, rounded up.
• Using an S-Break to interrupt a turn will make the user suffer only the normal delay of the S-Craft, discarding any delay they had before.
• Some attacks can inflict an additional base delay as part of their effects, which is added to the current delay of the target.
• Some skills can reduce the delay of allies to zero (AT Advance or Accelerate), making their turns happen immediately after.

However not all units take the same time to process the same base delay. Depending on their SPD stat, the base delay will be modified to obtain the real delay before the unit can act:
$Final\ Delay = 100\times\frac{Base\ Delay}{Unit\ SPD} \text{(rounded down)}$

Hit Chance

While arts and S-Crafts are guaranteed to hit, normal attacks and most crafts have a chance to miss and have no effect. The chance of an attack to hit depends on the attacker's DEX and the target's AGL:
$Chance\ to\ hit = 100\%\times\frac{Attacker\ DEX}{Target\ AGL + Attacker\ DEX}$

Damage

The formulas for physical and magical damage are the same, with the only difference being the stats used. Every number in each step is rounded down. A reflected attack considers the target to be the same as the attacker.

Sky FC

$Damage = 3\times(Attack\ Power - Defense\ Power)$
$Attack\ Power = [Attacker (STR_\text{ (Physical attacks)}\text{ or }ATS\times 1.2_\text{ (Magic attacks)})$$\times (1+AT\ Bonus) + Skill\ Power + Attacker\ Status\ Modifier$$+\ Random]\times Elemental\ Efficacy$
$Defense\ Power = Target (DEF_\text{ (Physical attacks)}\text{ or }ADF_\text{ (Magic attacks)})$$+\ Target\ Status\ Modifier)$ Where:

• AT Bonus is the STR Up Battle order bonus, which affects both physical and magic attacks.
• Skill Power is the power of the art or craft used (normal attacks have a power of 1). An S-Craft has an additional calculation: ${\textstyle Total\ Power = Base\ Power + Attacker\ Level \times(1+\frac{Level}{8})}$. If used at 200 CP, this power is multiplied by 1.5. Lorence and Colonel Richard also use this calculation (except the 200 CP power increase).
• Status Modifiers for the relevant stat are applied as the base value of the stat multiplied by the percentage the status effect active uses (e.g. 20% for Estelle's Morale), without taking into account equipment or quartz. Note that STR and DEF-affecting effects will apply to both STR/DEF and ATS/ADF.
• Random is a random factor. For enemies this factor is between 0 and 0.1×STR or (ATS×1.2) depending on attack type (with minimum of 2). For party members this factor is between -0.05×STR or (ATS×1.2) and 0.05×STR or (ATS×1.2), with a 1/11 chance of being between 0 and 0.1×STR or (ATS×1.2).
• A Critical hit (due to quartz or AT bonus) multiplies the final damage by 1.5.

Examples

Estelle has 100 base STR at level 24, and equips a weapon that gives her 80 STR for a total of 180 STR. With a normal attack her Attack Power would be 3×(180+1+Random)=516-597. If she were to attack an enemy with 80 DEF (meaning a Defense Power of 3×80=240) she would deal a Damage range of 276-357.

• If she installed an Attack 1 quartz in her orbment to increase her STR by 9 (5% of 180), her Attack Power would increase to 543-624, and her Final Damage range to 303-384.
• If she equipped a new weapon with 90 STR her Attack Power would increase to 546-630, and her Final Damage range to 306-390.
• If instead of a normal attack she used her Hard Break craft (30 Power), her Attack Power would increase to 603-684, and her Final Damage range to 363-444.
• If she used her Morale craft beforehand (20% base STR buff), her Attack Power would increase to 576-657, and her Final Damage range to 336-417.
• Lastly, if she did all the above her Attack Power would be 3×(100+90+(190×0.05)+30+100×0.2+Random)=720-804, and her Final Damage range 480-564.

In short, each additional point of STR from leveling or equipment adds 2.85 points to the minimum damage and 3.3 to the maximum damage of physical attacks, while each point of Power or in-battle STR buffs add 3 to both minimum and maximum damage. Note that quartz stat increases affect the total of base and equipment while status effects only affect the base number.

• If Kloe used Kaempfer on the enemy beforehand (-50% DEF reduction), their Defense Power decreases to 3×(80-80×0.5)=120, making Estelle's normal attack deal a Final Damage range of 396-477.

Each additional point of DEF from any source reduces physical damage taken by 3. Note that enemies do not use equipment or quartz, meaning status modifiers will always affect their total stat.

Kloe has 90 base STR and 100 base ATS at level 24. With Aqua Bleed (10 Power) her Attack Power would be 3×(100×1.2+10+Random)=372-426. If she were to attack an enemy with 50 ADF (meaning a Defense Power of 3×50=150) she would deal a Damage range of 222-376.

• If she installed an Mind 1 quartz in her orbment to increase her ATS by 5 (5% of 100), her Attack Power would increase to 390-444, and her Final Damage range to 240-294.
• If instead of Aqua Bleed she used Blue Impact (50 Power), her Attack Power would increase to 492-546, and her Final Damage range to 363-444.
• If Estelle used her Morale craft beforehand (20% base STR buff), her Attack Power would increase to 426-480, and her Final Damage range to 276-330.
• Lastly, if she did all the above her Attack Power would be 3×(100×1.2+100×0.05×1.2+50+90×0.2+Random)=564-618, and her Final Damage range 414-468.

Each additional point of ATS adds 3.42 points to the minimum damage and 3.96 to the maximum damage of magic attacks, while each point of Power or in-battle STR buffs add 3 to both minimum and maximum damage. Note that status effects affect according to base STR, not ATS.

• If she used Kaempfer on the enemy beforehand (-50% DEF reduction) and the enemy had 100 DEF, their Defense Power decreases to 3×(50-100×0.5)=0, making her deal her full damage.

Each additional point of ADF reduces magic damage taken by 3. Note that status effects affect according to base DEF, not ADF.

Sky SC and the 3rd

$Base\ Damage = 3\times Attack\ Power - 2.5\times Defense\ Power$
$Final\ Damage = Base\ Damage + Random$
$Attack\ Power = [Attacker (STR_\text{ (Physical attacks)}\text{ or }ATS\times 1.2_\text{ (Magic attacks)})$$\times (1+AT\ Bonus) + Skill\ Power + Attacker\ Status\ Modifier$$+\ Chain]\times Elemental\ Efficacy$
$Defense\ Power = Target (DEF_\text{ (Physical attacks)}\text{ or }ADF_\text{ (Magic attacks)})$$+\ Target\ Status\ Modifier$

• AT Bonus is the STR Up Battle order bonus, which affects both physical and magic attacks.
• Skill Power is the power of the art or craft used (normal attacks have a power of 1). An S-Craft has an additional calculation: ${\textstyle Total\ Power = Base\ Power \times (1+\frac{Attacker\ Level}{100})}$. If used at 200 CP, this power is multiplied by 1.5. Enemies do not use the increased S-Craft power value, only the base power associated.
• Status Modifiers for the relevant stat are applied as the base value of the stat multiplied by the percentage the status effect active uses (e.g. 20% for Estelle's Morale), without taking into account equipment or quartz.
• Chain is the Chain Craft STR increase: 0.1×Base STR for the second member, 0.2×Base STR for the third and 0.3×Base STR for the fourth.
• Random is a random factor between Base Damage/15 and (Base Damage/5 - 1). If Base Damage is 0 or less, Final Damage will be randomly 1 or 0.
• A Critical hit (due to quartz or AT bonus) multiplies the final damage by 1.5.

Examples

Estelle has 180 base STR at level 40, and equips a weapon that gives her 120 STR for a total of 300 STR. With a normal attack her Attack Power would be 3×(300+1)=903. If she were to attack an enemy with 150 DEF (meaning a Defense Power of 2.5×150=375) she would deal a Base Damage of 528, which results in a range of Final Damage of 563-632.

• If she installed an Attack 1 quartz in her orbment to increase her STR by 9 (3% of 300), her Attack Power would increase to 933, her Base Damage to 555, and her Final Damage range to 592-665.
• If she equipped a new weapon with 130 STR her Attack Power would increase to 933, her Base Damage to 558, and her Final Damage range to 595-668.
• If instead of a normal attack she used her Hard Break craft (30 Power), her Attack Power would increase to 990, her Base Damage to 615, and her Final Damage range to 656-737.
• If she used her Morale craft beforehand (20% base STR buff), her Attack Power would increase to 1011, her Base Damage to 636, and her Final Damage range to 678-762.
• Lastly, if she did all the above her Attack Power would be 3×(180+130+(310×0.03)+30+180×0.2)=1155, her Base Damage 780, and her Final Damage range 832-935.

In short, each additional point of STR (or Power) adds 3.2 points to the minimum damage and 3.6 to the maximum damage of physical attacks. Note that quartz stat increases affect the total of base and equipment while status effects only affect the base number.

• If Kloe used Kaempfer on the enemy beforehand (-15% DEF reduction), their Defense Power decreases to 2.5×(150-150×0.15)=320, making Estelle's normal attack deal a Base Damage of 583 and her Final Damage range be 621-698.

Each additional point of DEF reduces minimum damage by 2.67 points and maximum damage by 3. Note that enemies do not use equipment or quartz, meaning status modifiers will always affect their total stat.

Kloe has 150 base ATS at level 40. With Aqua Bleed (10 Power) her Attack Power would be 3×(150×1.2+10)=570. If she were to attack an enemy with 80 ADF (meaning a Defense Power of 2.5×80=200) she would deal a Base Damage of 370, which results in a range of Final Damage of 394-443.

• If she installed an Mind 1 quartz in her orbment to increase her ATS by 4 (3% of 150 rounded down), her Attack Power would increase to 582, her Base Damage to 382, and her Final Damage range to 407-457.
• If instead of Aqua Bleed she used Blue Impact (50 Power), her Attack Power would increase to 690, her Base Damage to 490, and her Final Damage range to 522-587.
• Lastly, if she did all the above her Attack Power would be 3×(150×1.03×1.2+50)=702, her Base Damage to 502, and her Final Damage range 535-601.

Each additional point of ATS adds 3.84 points to the minimum damage and 4.32 to the maximum damage of magic attacks, while each point of Power adds 3.2 points to the minimum damage and 3.6 to the maximum damage.

• If she used Orbal Down on the enemy beforehand (-30% ADF reduction), their Defense Power decreases to 2.5×(80-80×0.3)=140, making Kloe's Aqua Bleed deal a Base Damage of 430 and her Final Damage range be 458-515.

Each additional point of ADF reduces minimum damage by 2.67 points and maximum damage by 3. Note that status effects only affect the base number, which combined with every character's base ADF of 15, makes an ADF buff such as A-Crest be practically useless.

Ending Combat

Combat can end in various ways: the victory condition is met (usually defeating all enemies), the party runs away, time runs out or a defeat condition is met.

Victory

The victory condition for the majority of battles is the defeat of all enemies present. In other cases, only specific enemies need to be defeated. When the victory condition is met, the party is taken to the battle results screen.

Ending a battle with a victory grants the items and sepith dropped by the enemies as reward, as well as experience to characters not K.O.'d. The Monster Guide as well as enemy lists note the various rewards for defeating enemies.

The experience each party member gains from each enemy depends on the level difference between them and the enemy. For each level the party member is above the enemy, the experience is halved and rounded down, until a minimum of 1. In Sky SC and the 3rd only, for each level the party member is below the enemy, the experience is increased by 25% and rounded down, until a maximum of 9999.

Retreat

Most battles can be ran away from, with the exception of battles entered from scenes such as story-forced battles. The Run option can be chosen on a party member's turn, which will cause the battle to end without granting any items or experience.

Running away (if possible) is guaranteed to work, regardless of how the battle was entered. Afterwards, the enemy will flicker on the overworld, indicating combat cannot be entered again with that enemy until it stops flickering, or the chest from which the enemy appeared will remain closed.

Defeat

The defeat condition for the majority of battles is all party members being K.O.'d. In other cases, NPCs accompany the party and the battle ends in defeat if any of them are K.O.'d.

In most situations a defeat results in a game over, with the option to retry the battle or go back to the menu to load a save. Some battles allow for a defeat that doesn't result in a game over, with victory being optional for bonus rewards or the outcome not affecting the story. Items and experience aren't granted in these cases.

Time Out

In very few cases the battle has a time limit. If a certain amount of AT passes without reaching either a victory or defeat condition, the battle will end without warning or granting any rewards. In these cases victory before the time limit is optional for bonus rewards.