Iron Spider

The iron spider can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.

The iron spider is incapacitated while in the area of an antimagic field. If targeted by dispel magic, the iron spider must succeed on a Constitution saving throw against the caster's spell save DC or fall unconscious for 1 minute.

The iron spider shoots out a 6-inch-thick web cable up to 50 feet long, attaching the far end of the cable to a solid surface up to 50 feet away from it. As a bonus action, it can detach the other end of the cable from itself and attach it to a solid surface within 10 feet of it. Once it creates 200 feet of web cable, the spider can't produce any more cable until the next dawn.