I'm hoping someone can give me some advice on how to defeat her because I'm having a heck of a time. None of my standard weapons work against her and I figured out I probably need water based attackers(?) but I only do minimum damage and barely make a dent before my pet is defeated. I only have a tier three pet (level 97) so maybe I need to boost my pet up more before I try again?

Any advice and help is beyond greatly appreciated!

has written up a pretty helpful post HERE. It basically covers everything about forj.

Although you could normally expect a tier 3 pet to beat an opponent with 625 HP/325 attack/400 defense, Forj Matriarch is a strange challenger in that she is much stronger than her stats advertise (the same can also be said about her strongest form, Erupting). I'd say at least tier 5 is appropriate for defeating her the first 10 times. She even becomes easy at tier 6 thanks to blunderbuss.

Thank you, in fact he was kind enough to post on here :)

Yeah I kind of figured I was currently out of my league. I'll definitely be getting blunderbuss and checking out your guide that Andrew suggested.