twitch.tv/SprinkleBeard
We will cover MULTIPLE versions of how to complete spider.
Beginner: Focus on massive wave clear against the affinity you are fighting, and use Void champs with aoe clear to help accomplish this til about Spider 10.
Intermediate: 2 x ColdHeart strategy. Using CH's A3, space them out and never let the queen get a turn. Burst her down w/ things like Weaken and Def Down. Best used from 15 til about 20, although, you can use it earlier (maybe as low as Stage 10.)
Master: HP Burn ALL the little baby spiders, and do enough damage to the boss so that as each of the babies gets a turn, 10 x 3% of her max HP will burn her down the rest of the way!! I have yet to reach master myself.