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.
the first time gorr had to retreat and take the children insted to bait Thor
The second time gorr was amped by the shadow in the shadow realm which is located in a galaxy with infinite darkness(https://marvelcinematicuniverse.fandom.com/wiki/Shadow_Realm)
The third time Thor didn't posses stormbreaker which means that he was weaker and also enchanted many children with his power which means that he basicly shares it and makes him weaker