Its just dumb that she alone is able to take down an entire party, the "attack me if you dare and i'll poison you badly" is broken, first venom is too potent, your life bars gets drained like there is no tomorrow, second, i can understand in fantasy and lore that arachna have poisonous skin and whoever attack her gets poisoned but that should affect only those who attack her in close combat hand to hand, so blood spills and poison can affect the attacker, why Gale is poisoned when she shoots her arrows, maybe the arrow that hit arachna and got poisoned returned magically to gale to poison her, also is useless to take magical characters as many of them have basic attacks pshiscials, so poison to you too, yeehaaa!
So
1. Reduce damage from poison
2, Make it only affect close combat characters, (tanks)