Apo, Armiger, Mordecai, Lodric and one more turnmeter reducing champ (if you have, I can't recognize every champ by the picture, as Plarium adds new ones every now and then).

Mordecai puts HP burn on every Spiderling. Then you just have to wait that they burn the big spider to death. Apo makes you faster and can heal. Lodric can shield your team and remove debuffs (poison). Armiger and, if you have one more champ with turnmeter ability, this champ prevent the big spider from getting a turn.

Before you think about Spider you should do more 12-3 campaign. A team without lvl 60 champ won't do high dungeon stages.

I wouldn't bother leveling Lodric. He's really not that useful overall.

Ninja's fantastic for spider. AOE freeze is really, really good. I'd probably do something like Ninja, Armiger, Royal Guard, Achak, Mordecai. You should be able to lock the queen down with Armiger and Mordecai, and Ninja will AOE freeze the spiderlings.

I wouldn't bother leveling Lodric. He's really not that useful overall. 

Decrease atk debuff on A1, paired with team shield and cleanse = CB.

Team shield lasting 2 turns on a (booked) 2 turn cooldown = Scarab King.

For Spider I just recommended him as I don't see any other cleanser on this roster. Spider is probably not the part why you would build Lodric, but he can help here. That his cleanse is only single target is no problem at Spider, as the little Spiderlings tend to attack the same target. 

But not usefull overall? With the roster the OP showed us here? I think, Lodric would be my next 6*, especially for CB content.

Scarab King is not something I would really bother with at this stage for OP. But that's fair.

As for CB - two of his three moves do literally zero damage. That's a massive loss of damage. You'd definitely be turning off his A3 on CB. He can sub in as a stun cleanser, yes, but you can't rely on him for ATK down, because it is only 60% chance to proc (65% with Sniper). That's not nearly consistent enough. Overall I would not expend resources on him, he's very replaceable.