So, to begin with how power scaling is going to work between Shirou and the DxD world, I'll be using servant parameters as a basis for this. As of right now, Shirou has the same stats as Archer, but some are altered due to his Double Summon skill, via his connection to Muramasa. Just check my profile if you want to see the extent of bullshit that I've come up with for setting Shirou's stats, skills, and Noble Phantasm(s) with.

So, to recount, there are set rules for servants. Each having a letter to E-A and having a number that equalizes to a multiplier when comparing the average human to a servant.

E: 10

D: 20

C: 30

B: 40

A: 50

EX: Immeasurable (As far as I've read the wiki)

Yes, I've read the entire 'Parameter Rules' page just to understand this. The numbers are a multiplier for a base. Meaning that E is ten times better than a regular human. And A is 50. So, for example, if you take the highest speed a regular human can reach, which is 27 ½ miles per hour, or if you're taking an Olympic athlete, it's 30 miles, but some have been recorded to reach 40 even. So, in order words, take that number and use a parameter number from E to A and multiply it.

Using Cu Chulainn's rank A speed, and multiply it with 30 miles for example, it's 1500 miles, easily breaking the sound barrier.

Not to mention the "+" and "-". To try and make this easier, having a + sign means it is doubled for a temporary moment and having ++ means it's tripled and so forth. So, if we put it like this, B+ is weaker than A, but it can be on the same level as an A rank for a temporary amount of time.

And having – means it is "not reliably stable" in the page's words, but I'll put as being two times weaker and it goes on the same as the + sign. So, B- is 35 while B—is 33 or something. I get it it's stupid, but they do say it is "for no particular reason".

And to count EX Rank, it means it is just on a level on its own or league as some put it, but I'm leaving it at that. It can also go by other signs as well. Most notable ones being "?, -, " They just mean EX, but catering to their own unique reason why they have that.

Just reiterating, having a + or – goes something a little like this,

E: 10, 20, 30, 40, 50

D, 20, 40, 60, 80, 100

C: 30, 60, 90, 120, 150

B: 40, 80, 120, 160, 200

A: 50, 100, 150, 200, 250

I used 'Sent to an alternate DxD world with a Mystic Eyes and Servant-trix's rules for parameters, just because it's easier for me as a writer. Just having someone else do the job is just easier for me.

To compare Fate's servant parameters to High School DxD's it goes a little something like this:

E: Low Class Devil

D: Mid Class Devil

C: High Class Devil

B: Ultimate Class Devil, High Level Dragons, Tannin (He's stated to be a Ultimate Class Devil even though he was a Dragon King)

A: Satan Class Devil, Regular Gods, Buddhas, Dragon Kings, etc.

EX: Primordial Gods and "King" Gods, Heavenly Dragons, etc.

So... The idea is pretty stupid to say the least, at least for Servant Parameters of course, but don't worry about it. When I said that Shirou will need his new servant parameters to live in this world, I meant it. But I'll state his power for now.

Shirou's Parameters (Present):

Strength: C+

Endurance: B-

Agility: B

Mana: B

Luck: E (Of course)

NP: EX

So right now, you can see why and how he decimated an entire underground black market just by seeing the scaling. Having something similar to an Ultimate Class Devil's stat, but anyways I think I've gone way too far out of line at this point. Just always remember that these parameter rules are stupid.

Alright, this is Axngelus, my brain is fried and watiting to write the next chapter, so Peace Out!