The hooks on his palms and feet enable him to climb up walls and across ceilings, as if under the effect of a spider climb spell. He has a +8 racial bonus on Climb checks and can always choose to take 10 on Climb checks even if rushed or threatened.
A chitine has a +1 bonus to Armor Class, a +1 bonus on attack rolls, and a +4 bonus on Hide checks, but his lifting and carrying limits are three-quarters of those of a Medium character
Eventually these alterations became permanent, resulting in a race of spiderlike, four-armed humanoids that can build with webbing in the same way that humans employ stone or wood. The drow selectively bred and magically meddled with their slaves, incorporating ghastly “improvements” as well as the results of fumbled experiments. Once their ancestors were humanoid in form, but their enforced slavery to the drow entailed more than simple execution of duty. The spiderlike chitines exemplify the unnatural changes that can be incorporated into a humanoid with the aid of evil-inspired magic.