Hi,

At this stage there are 2 possible ways to go about it.

If your nukers can still nuke the spiderlings, than you can make a nuker team and push through with aoe nukes. This will not work in later levels tho.

Otherwise I would recomend to take out your champ in lead position (cant remember name) and put apothecary as your lead. Level up Ultimate Galek with a lot of accuracy and put him in as fifth. Build Stag knight as your tank with a lot of defense and resistance. 

Deciding who is tank depends on 2 things. First is affinity. Champions who are weak affinity will allways be targeted first. So in this case if boss is blue, then it will prioritize green affinity. Second thing is champion HP. If you have 2 champs with green affinity the target will allways be the one with lower HP. So Stag knight will not work as a tank against red affinity stages. because the spider will avoid him for he will be strong affinity. So you will have to use someone else for that.

I would probably also relace the Reliquary Tender with Armiger (needs a lot of speed, accuracy and 100% crit)

Hope this helps. 

Lyssandra with her A2 (as well as Armiger) will have problems to land their turnmeter skills at this stage due to their weak affinity. The chance to get a weak hit is 35%, weak hits can't land debuffs or turnmeter effects. Lyssandra's A3 will still work, as it doesn't hit. 

Stag Knight will have problems to land his def debuff for the same reason.