Dmg reduction is bugged

[Terrorshock1]

Example: pet:groudy passive "reduces damage by 8%" *pet hits target* my damage goes from 2481 to 1800/1900
this isnt 8%
I also tested with other pets that did dmg reduction like slag ellie breezaga their passive claims to do 10% but its doing 25%

am i missing something here?

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