During the fight it will be surrounded by other spiders that only make the battle annoying. Often it will trap a character with its silk and begin to pull them towards it. You can use Zael's Gale attack to break them free. If Zael fails to tear the silk, the spider will swallow its prey and remove him or her from battle. Party members who have been swallowed will return after the spider is defeated. It also launches paralyzing spikes. It's weak against fire, so Yurick makes the fight against it a lot easier.
If you happen to have the Grand Swell weapon, it makes the fight much easier as you can hit the front of it and still cause full damage.