AOE burn – This is a common strat which you may need to pick up as you progress through levels in Spider. The idea behind the AOE burn is to burn the spiderlings because the boss takes damage every time the spiderlings attack from. This is very effective in chunking the spider slowly.
The key points for this to work are to control turn meter on the boss spider so that it doesn’t eat all the spiders and heal up. You can place a debuff such as stun or freeze on the spiderlings, this is useful because the debuff will prevent the spiderlings attacking but they still take the burn damage along with the boss spider.
Using this method you will be able to avoid the poisons that the spiderlings place. Two of the best champs to use for this are Ignatius and ultimate Galek as their hp burn is AOE and is very effective in burning the spider.
For the stun, you can have someone wearing stun gear or someone with an ability to do it. It isn’t essential you have the stun or freeze, however, it will help the run and boost the run time.