Gleaned from a book of esoteric knowledge:
The Spider's realm is not primarily a place of obvious dangers (though there are some of those), it's a place of allowing you to trap yourself by reaching for things that you want; a place of misdirection and double meanings. As such, a strike force may be a little too straightforward, and may well end up imprisoned as well. Many of the spirits there think themselves independent, and have their own agenda which proves to serve the Spider without their knowledge. Other spirits seem anomalously out of place - cheery and helpful - and it is not clear why they chose that realm. Of all the Great Spirits, the Spider is probably the one with the most *prisoners*, as he likes to keep his enemies alive.