The Let's Play Archive

Etrian Odyssey

by Crosspeice

Part 43: Damage Formula

Side Course 2: Damage Formula

Best to get this big boy out of the way early enough. With an intense numbers game such as this one, it's pretty good knowing exactly how this game ticks. And, uh, that would be nice if we did, but we don't know everything. Still, we have the formulas, so let's start at what stats are used for attacking.

[STR + weaponATK] * Pwr% * Elem% * PhyAtkBoost%

First up is the ATK stat, which is determined by your STR + Weapon ATK. You can see this number on the status screen easily enough. This is then multiplied by a number of factors. The biggest one is Skill Power, which is usually higher than 100% so it has a bigger kick than using a regular attack. Next is Elem%, which is your resistances to a specific element, physical or, well, elemental. Yes, this DEF related multiplier is actually in the ATK part of the calculations, meaning these are factored into the formula BEFORE any DEF related boosts are applied, meaning they have the biggest difference on the numbers.

Now for the various ATK boosts you can have, ranging from your own skills, passives, buffs and debuffs. Note that weapon masteries don't actually power up the skills, but instead the Weapon ATK, so upgrading your weapon can make a difference. The ATK Up skill on some classes boosts your STR, including STR bonuses on your weapon, so those are also a good pick. Since this is where debuffs are applied, it's preferable to have something that reduces STR (and therefore ATK) to something that increases VIT (or DEF), since the STR reducing number is applied first and has a much bigger effect on enemies as STR numbers reach over 500, while VIT, along with most other stats, barely get past 100 for the most part.

[TEC + weaponATK] * ElemDam% * Elem%

Next is something you don't see very often since it's only used for composite attacks. Well, for the Ronin skills of Orochi, Raizuki and Hyosetsu, and the THREE enemy skills that are composites. The Troubadour skills of Blaze, Frost and Shock don't use this formula since they don't buff the damage dealt and give you an extra attack, simply change your weapon to a specific element. Same for the Oils, as they're LV1 versions of those skills. Yeah it's annoying, but this does mean a Ronin using these skills is technically attacking twice and hitting juicy elemental weaknesses, so it's something neat. Unfortunately, this uses the Ronin's awful TEC stat, naturally capping at 53. The ElemDam% is the elemental power of the skill, ranging from 50% at level 1 to 100% at level 10. And again, Elem% is how well the enemy resists that particular element. Weird how this is used for six skills total, but hey, that's this game for ya!

[2*TEC + (spellATK * Mastery)] * Pwr% * Elem% * MagicalAtkBoost%

Alright, enough messing around, here's the big one you need to see. This is only used for the Alchemist's elemental skills, being the only class that has them, and any enemy that uses a pure elemental attack. I hope this shows how important TEC is, since it's where most of your damage comes from. As stated in the Alchemist write up, the second half of spellATK*Mastery is basically negligible due to the small numbers involved. For the basic skills, spellATK is 10, and for the stronger skills, the spellATK starts at 10, but then decreases to 6 as you level it up, which is just ridiculous. Mastery is the boost provided by the elemental mastery skills and cap at 130%. So the most this number will ever be is 13. Added onto 2*TEC, which can get as naturally high as 150. This is why you don't bother levelling up your masteries past when you need them, they do absolutely nothing for you.

You should still level up your strong spells, as their Skill Power gets as high as 350% for the strong single target skills, which more than offsets the spellATK of 6. Ohhhh nooooooo. Elem% is as before, though since you're using elemental weaknesses this time around, they're usually a lot more friendly to you to increase your damage even more. Most major enemies has at least one element they're weak to, so using all three elements over the course of the game is definitely worth it. MagicalAtkBoost% isn't actually used to, you know, BOOST your elemental damage, since there's no skill that does that. It is used ONCE, however, by an enemy skill that will debuff your elemental damage. This is seriously the only time this modifier is used.

STR DEF: 50% * (VIT+Armour DEF) * DefBoost%
TEC DEF: 25% * (VIT+Armour DEF) * DefBoost%

Now with that ridiculousness out of the way, we move onto DEF. It's as simple as it looks, though TEC DEF starts much lower to vaguely offset the 2*TEC. Weird. Anyway, DEF is determined by your VIT + Armour DEF, which will result in lower numbers due to how mediocre armour is compared to weapons, especially since no skill boosts an armour's DEF like they do a weapon's ATK. DefBoost% is simple enough, though this only applies to skills and buffs and debuffs and passives that affect the DEF stat, anything that affects the ATK stat fall under PhysAtkBoost%. It's impossible to know which defensive skills are either DEF boosts or damage reductions without looking at the data, as a skill like DEF Up is a damage reduction while Escape is a DEF boost. The game acts like Shields is the same as DEF Up, but that reduces elemental damage. Because of course it does.

Base Damage = ATK - DEF

Okay, now that we've worked all this out, we have our base damage from the new ATK and DEF numbers ran through the formula. This is why reducing ATK is much better than boosting DEF, as making the much larger number on the left smaller makes the DEF subtraction much more substantial. There are a few ways these can be modified: if an attack is a critical hit, DEF is reduced to 0; party members in the back have their DEF doubled (which become less impressive the scarier the enemy attacks become) and Boost doubles a regular attack's base damage, or increasing a skill by 5 levels.

If ATK <= DEF: Damage = Random(1 to 5), skip all further Random Variance steps

Finally, we'll be going over the damage variance this game has. Because depending on how the ATK and DEF values match up depends on how much variance you have and which kind. This shit is bananas yo. This explains why your back row Medic sometimes does really pitiful or kinda pitiful damage against Clawbugs and such.

If ATK <= DEF * 1.1:
....Base Damage = [Random(8 to 12) * ATK / 100] (for STR-Based attacks)
....Base Damage = [Random(8 to 15) * ATK / 100] (for TEC-Based attacks)

We need to reach a positive Base Damage number to finish up the formula, so when your ATK is just barely higher than DEF, instead of making it a really low number, like if your ATK was lower than your DEF, the game gives you a fairly low, but variable Base Damage to use for what's next, which is kinda nice, I guess.

If Base Damage <= 100:
....Damage = Base Damage + Random(0 to 5) (for STR-Based attacks)
....Damage = Base Damage + Random(0 to 10) (for TEC-Based attacks)

Pretty simple, just a little extra variance thrown on for when ATK is slightly higher than DEF and the final formula you'll see for most of the game with enemies around similar level to you. Like with spellATK, the variance is pretty negligible, regardless of what type of attack is being used, so you can mostly figure out the damage from the Base Damage with a bit of a small bonus thrown on.

If Base Damage > 100:
....Variance = 5 * [Base Damage / 100] (for STR-Based attacks)
....Variance = 10 * [Base Damage / 100] (for TEC-Based attacks)
....Damage = Base Damage + Variance

When you're much stronger than your enemy, or at least have a lot of buffs compared to their VIT stat, then the variance gets slightly more interesting, though it's heavily dependant on your Base Damage to even make a dent. But this really starts rolling allowing you to easily deal ridiculous damage to enemies you're way stronger than. Oh, that's not really very impressive, but hey, it's something.

And there we go, that's how you deal and take damage. Uh, pretty simple, really, and definitely something we'll remember as we go through. Well, the main thing to remember is that some buffs and debuffs just aren't worth it due to how they're plugged into the formulas, and ATK is much easier to increase than DEF due to the disparity in stats, so it's therefore much more worth reducing if you want to take less damage. Crazy, I know.