The Superhero Database Classification number, or SHDB Class, is a number that represents the overall 'power' of a character. All traits of a character are used for calculating the Classification.
What it DOESN'T mean
This doesn't mean that a higher class would always beat a lower class character. But the bigger the difference in Class is, the more obvious it is who'll win in a fight.
How is this calculated
( INT^1.3 + (STR*0.5 )^2 + (SPE*0.5)^2 + DUR^1.6 + (POW + (SPS*SPL))^2 + COM^1.8 ) ^ TIER
Super Power Score and Level
Every Super Power has a score (SPS) that is used to calculate the Class. Each Super Power also has 3 levels (SPL). The level is set when connecting that Super Power to a character. The level determines the final score, of the Super Power, being used in the calculation.
In the originals it was freya’s power (with a little preparation) that allowed her to remove upgraded vampire Lucien’s power (Freya was not powerful than finn ever was so she’d be tier 2 as well).
Freya was also able to create a dagger capable of killing upgraded marcel using her own blood and a few other things. Blood is used to amp magical spells
“Witches can integrate the use of blood into their magical practice to strengthen certain types of spells, which range from simple and minor locator spells to more powerful and complex curses and hexes whose effects can be so devastating that they can even kill a human or supernatural creature.” https://vampirediaries.fandom.com/wiki/Blood
Klaus would scale to upgraded marcel as he can keep up with him and even snap his neck (which takes more effort).
Lucien would be tier 2 as he no diffed klaus and would also be able to do the same to marcel.