The spider leads him in circles, enough that he's starting to think he's not got the spell's parameters right, but then he finds himself at the entrance to a park. A very big park. What a darkling would be doing here, he has no idea, but the magic in the spider is very insistent this time.

So he parks the car and climbs out, looking around. He has no desire to pay any entrance fees, so he just flicks himself into ghost form and drifts invisibly through the gates, in search of the source of the darkling magic. The spider gets levitated over his palm, and he goes slowly, to feel for the direction of the magic rather than having to watch it.

He sees the bison before the person. Jesus Christ, those are big.