You probably didn't notice, but the spider with 138, which I killed easily at level 3, will use the "blink" ability everytime to put herself atop a spider web.
If you burn/destroy that web, she falls prone and takes around 38 dmg everytime she does it.

So... easy peasy. Just gotta play smart and as it was said, use the terrain/elements. It died pretty fast after the third "blink" on a web