[Brefaisil]

The web is quite a bit stronger than it would initially appear to be; Marcie may recall a certain tidbit about spider silk having five times the tensile strength of steel by weight, and Fraochun is spinning webs from much thicker strands than your average spider.

What's more, this web in particular seems to be partially affected by a temporal freezing effect, rendering it close to (but not quite) immobile. Marcie's probably seen this before; for a given object, external forces can be used to displace it, accelerating it as a function of distance over time. The amount of force necessary to produce a given velocity is also a function of time; the less time used, the greater the force must be, and as the change in time approaches zero, the force necessary approaches infinity. But time isn't passing for this web, or if it is, it's passing very slowly... the amount of force needed to push it goes on into absurdity, most likely.

Marcie might be able to infer what happened now; Fraochun was temporarily displaced from regular time, freezing the world around her. This gave her an opportunity to move unimpeded, but thanks to that freezing effect, she wouldn't have been able to harm Marcie directly, so she's settled for laying a trap instead. She seems to be experiencing a snapback now, being frozen herself to make up for the time she skipped.

Thankfully, that also means Marcie's only concerns (other than smacking into a strangely rigid and unsticky spider web) would be the throng of distracting spiders chasing her. By now, a few will have managed to scuttle up the web and onto her feet, crawling up toward her torso. Unless she's comfortable with self-immolation, setting them on fire isn't going to be an option.