combat while climbing

[Thac0 Redeye]

I'm hoping someone can direct me to rules for combat while climbing. Soon my players will have to deal with this. They are in the underdark and will have to climb down a sheer rock face using a giant spider web the drow have ultitized as a way to transverse between levels in the area. Like a large cargo net attached to a wall. They may have a fight with some drow while trying to get to the next level down. I know they loose dex mod and shield to AC and cant use more than one hand to attack, but are there any other modifers? Do they have to make climb or some other skill check?
thanks

[Elder_Basilisk]

https://www.d20srd.org/srd/skills/climb.htm

You've got the basics. But you also have to make a climb check every time you take damage or you fall.