The Spider Lady is found in the Top Secret Facility or TSF for short.
This boss is fought in two phases.
First phase has her jumping around the room, causing shockwaves upon impact. Expect extreme knockback from it if you're caught within range of this attack.
Besides her constant jumping around the room, swiping with her legs or the frontal pincer crushing attack with her teeth, the first phase may not seem threatening. The same cannot be said for the second phase of the battle
The second phase starts up when she reaches 50% or below of her health bar, upon which she can cast multiple spider webs that inflict Paralyze on you if caught. Each web causes 8 seconds of Paralyze and this boss is capable of launching multiple layers of webs, rending you immobilized for a prolonged time. The webs aren't only attacks that makes this second phase of the battle threatening, it's her ability to summon forth her spider minions.
Comboing off the layers of spider webs, the Spider Lady has the ability to call upon the mini spiders within the area. There are at least 100+ mini spiders that will be alerted to your presence if you are ever caught in the web attack, each of them dishing out 170 physical damage per hit. Being paralyzed while being constantly swarmed by mini spiders will result in an instant death.
As threatening as the second phase of the boss battle may be, there is a way to avoid the mini spiders swarm even if you are ensnared by the layers of spider webs. The solution is to stay within the green puddle area and always fight the Spider Lady when she's within the green puddle area; as the mini spiders do not traverse over there. Avoid standing on the dirt ground in the Boss Room when she enters her second phase.