Ultimately, Bilbo's entire plan to rescue the Dwarves is dependent upon the One Ring, which makes him invisible when he is wearing it. But when he rescues his companions from the spiders, he does have a few other tricks up his sleeve. When the spiders took his friends, they did not take Bilbo, so he woke up alone in the forest; thinking that the Dwarves simply left the path, he went to go look for them, which is when he found out that the spiders had taken them captive. In order to get his friends back, he put on the ring and started to sing insulting songs at the spiders, calling them names, and they went off to go look for whoever was insulting them - but since Bilbo was wearing the Ring, they could not find him. While still wearing the Ring, Bilbo started killing the spiders by throwing rocks at them (Hobbits were known for their good aim) and by stabbing them with Sting (his sword, which he got from the Troll hoard). He then freed the Dwarves and they fought to kill all the spiders.