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.
ok how about this, no overpowered items. in this category i'd personally put mario against the hero of legend as the hero of legend has the most items and can compare to mario's item arsenal pretty well. i'd think it'd be very close, but the hero of legend would win as if mario tries to just do a jump, link could easily block it with the cane of somaria. i guess the only trouble link would have is mario's power-ups don't have a limited supply, as link's bow can run out eventually and force him to find more arrows.
let's put mario vs the hero of the wild. that would be interesting, and we'll be including every item literally ever except for anything that makes them permanently invincible (super stars are fine, i just mean like the invincibility leaf) so first off, in terms of strength, mostly mario has the advantage here. mario can lift castles as seen in super mario world when he defeats larry, mario has been able to alter GRAVITY to his advantage as seen in super mario galaxy, and mario can outrun bullets and run up walls with his speed. the hero of the wild mostly has a disadvantage in this area, as there are no super strength items in botw, only items that make his attack go up (also there probably are, but its like 3 in the morning so im too lazy to check) so link loses here. now experience, however, link crushes mario here. link fought in the great calamity (and legibly lost dont hate me) and protected the princess zelda until he was wounded by her on accident and technically never fell in battle, and eventually came back 100 years later, still in prime, not looking, feeling, or acting old in the slightest and was able to defeat ganon and eventually dark beast ganon, a demon made entirely of hatred. mario has been fighting too, but the only times hes actually ever really hurt the enemy hands-on is like super mario galaxy and a couple other titles, as most of the time mario uses his environment and anything around him to his advantage (the infamous bridge switch, throwing mecha-koopas in mario world, etc.) so in terms of fighting experience, link takes the cake here.
honestly, and it's pretty boring but it's true, it always depends on where they fight, how much prep time they have, what items are available, and obviously which link mario fights. this is pretty tough, though, so don't get too worked up over what i said as my opinion doesn't matter.