The factors of what determines an S rank is split between 5 categories

• Clear Time
  
• Orbs
  
• Stylish Average
  
• Damage
  
• Item used

Most of these Categories are Self explanatory

Clear Time is determined by how Fast you beat a Mission, This one shouldn't be a problem most Devil May Cry games are very generous in how much time you are given for S ranking a mission. Once you beat a mission and know it's in's and outs, then Clear Time shouldn't be an issue very often.

Orbs is simple enough, the higher the amount of Orbs you collect by the end of a mission, the higher your Orb Rank will be. The trick to obtaining an S for your Orbs rank is to reach Show Time!! In combat. Like any Devil May Cry game, the higher your Style Rank upon defeating an enemy, the more orbs they will drop upon defeat. If you can consistently defeat enemies at Show Time!! rank then getting an S rank in Orbs should be no problem. Although If you're only Spamming guns and remain at Don't Worry Rank for an entire mission then your Orb Pay out and in turn your Orb Ranking won't be very impressive.

Stylish Average while a little confusing at first, is actually exactly what it's titled. It is the ending total of all the combos you preformed in a level. Once your rank disappears off-screen that is considered the end of your combo and that rank is added to the ending average.
A Show Time!! Rank raises the Average the most, and a Don't worry, Rank will lower it the most.

Damage is simple but also the most unforgiving. To obtain an S rank, you can't be damaged a single time though out the entire level. Depending on the difficulty, an A rank can also be pretty tough. Most of the time you can only take a single hit on DMD another will bump you down to B, and sometimes an attack can be so powerful you could get bumped down from S to B in a single hit.
Obviously, the most effective way to get an S rank is to prefect the level, and take no damage.

Item used should be the easiest category to get an S in. Simply not using any items will give you an S, but to explain further depending on the Item used that will bump your rank down a certain amount. For example, a Devil Star will only bump you down to A rank, you can even use more than one, but a Gold orb will bump you down to B.

Your Final Devil Hunter Rank is determined by adding up all the Ranks from the 5 categories.

Thanks to LonerHero for supplying and organizing this detailed info from DMC2's official Japanese guide here https://docs.google.com/spreadsheets/d/181xUd1Ci2lTZCMRst57Qw6rTiPCGhwtJCC9dAa2dGiA/edit#gid=0

And thanks to Whitelion for the Translation of the guide.

The Stylish Average, Damage, and Item Used Categories remain the same between every level

So I will list only the Clear Times and Red Orb requirements for each mission

These Clear Times and Orbs have been taken from the Official Japanese DMC2 player's guide

Dante Disc






Lucia Disc

Here is a Link to a table listing the Stylish Value of every attack in the game, as well as other Technical information, done once again by LonerHero

https://docs.google.com/spreadsheets/d/1_pQ4jhMW53OUNsjOFaOjSqk8TMrtvhI1nPLDiJNIdGU/edit#gid=1932583262



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Getting to Show Time!! Rank in combat isn't too tough once you've gotten the practice in, the most useful thing to know is that dodging will freeze your Style rank and keep it from fading. So if your not close to an enemy, you should be dodging until you have an opportunity.

The Unlimited Devil Trigger Code does not interfere with your End level ranking so feel free to use it if you wish, Abusing the Chrono Heart can be pretty fun.

The Devil Trigger Hearts actual have different functions
The Electro Heart gives your attacks a wider hit box and has your DT drain a bit slower.
The Flame Heart adds allot more active hits to your attacks, really increasing the damage
and The Frost Heart adds a freeze to attacks, Enemies will freeze in place when damaged, have this paired with the Chono heart and most enemies don't stand a chance.

If an enemies' health is depleted, but you still managed to hit them with a melee attack before they hit the ground, then you get a huge style boost, I'v only managed to do it a few times against Blood Goats using the Chono Heart. It's pretty tricky to do, but it's worth knowing.

Holding down the Right Trigger or R2 will disable the automatic lock on, this is useful for when you just want to hit switches and not fight enemies

Boss fight only levels can be Tricky to get orbs on, for most bosses you're going to want to make sure you end the fight at Show Time!! And stand as close to the boss as you can, sometimes the orbs the bosses drop upon defeat are the only ones you can get in the whole level. But in some cases the boss won't drop orbs, when that happens you need to collect the Green Orbs around the boss arena, Green orbs will only be worth Red orbs if your Style Rank is high enough. If your rank is too low, they are worth nothing.

Dante's Mission 18 can be tricky to S rank when it comes to Style Average, during the first half of the level, I recommend getting to Show Time!! And collecting the Green orbs around the arena, and then continue to get to Show Time!! And let it fade away a good number of times so your Average is high. The fight with Dispare embodied makes it tough to keep a good Average.

Lucia's Mission 5 is tricky to S rank since you stuck with the Evil Heart which drains your health and counts as damage, it's impossible to get an S in the Damage category, but if you use unlimited DT and the Healing Heart you can negate the effects of the Evil Heart save for the first bit of damage it will do to you.

Lucia's Mission 7 is extremely hard to S Rank. For a while I thought it was Impossible. Thankfully I found this video by This DMC2 Player Javelina Devil


As shown, Trish when in Devil Trigger is the only one capable of attacking the Fish Boss Tateobesu fast enough to gain enough style to reach Show Time!!
It's actually impossible to S rank this level with Lucia unless you do the Secret Mission first to grind out some Show Times.

Javelina Devil is a great source for DMC2 S ranks if you need reference material on how you should play.

Last this is just a Mod I made if anyone is interested

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And with that it's the end of my Guide. I hope this can be useful to anyone interested in delving a little deeper into DMC2.

See you later and remember to Keep It Stylish