RebornRanger

Also gigalith with sand stream was how I beat her. if you dont mind raising up a gigalith and lycanroc those two should be able to take care of her, especially if you can get hawlucha and avalugg to do some damage with the strategy above

do you have any mons in your pc that are decently leveled?

metagross with bullet punch was a godsend for me in this. if you can get a beldum and raise it priority STAB hits hard

theres also repeatable trainers you can battle at agate circus that make it decently easy to grind so if you give your noivern an exp. share itll take no time at all and you can level up your other guys too

early game mons that really helped me were numel, blitzle and mightyena. theyre all available pretty early and really help in the early gyms

honestly your best bet is to grind up a roserade (i'd use the repeatable battles in the grand hall) it wont take too long and roserade with grassy terrain/giga drain can do some serious damage to her

I used ninetales(drought), venusaur(chlorophyll) and roserade to beat her. your lilligant can easily replace venusaur but i would recommend setting up grassy terrain/sunny day (or a mon with drought). taking her field advantage is key (grassy terrain for that) and setting up sunlight weakens her moves. if you'd rather use your manectric with electric terrain you could try using a heliolisk to get the electric boost and to nullify any water attacks (dry skin) or set up sunny day (use solar power for this) and let heliolisk and lilligant sweep in the sunlight.

grind up your trapinch for sure, great movepool and really useful for some upcoming gyms. maybe catch a yamask from shades gym and train that up, cofagrigus with mummy can make a lot of opponents useless. wont be available for a couple gyms but get an escavalier as soon as you can

lose the manectric for her gym I'd say. you could try raising a walrein for her garchomp and have it hold lax incense/quick claw and soft reset until you get a blizzard off. Also try raising a roserade with grassy terrain, itll take away her field and make her seeds pointless, also helps a lot with later gyms.

my current team switches around a lot but all roughly lvl 90 Greninja (Surf/dark pulse/ extrasensory/smack down) Bashful, protean, choice specs Metagross (zen headbutt/bullet punch/stomp tantrun/ice punch) Adamant, clear body, Metal coat Garchomp (dragon claw/stamp tantrum/fire fang/iron head) Adamant, sand veil, draco plate Mimikyu (play rough/shadow claw/trick room/destiny bond) adamant, disguise Roserade (giga drain/grassy terrain/venoshock/dazzling gleam) Modest, poison point, big root Kommo-o (dragon dance/drain punch/poison jab/drago