Spiderbane is a Side Quest in Sword Coast Legends. You can start this quest by completing Sticky Situation.
- Ask the merchant about Malyss Root
- Bring the root to Andra
- Obtain a piece of troll fat
- Obtain a spider venom sac
- Gather some fresh Id Moss
- Return the ingredients to Andra
- Check in with Yenrry
- Investigate the altar in the swamp
- Enter the hidden chamber
- Find Andra
Walk over to Davtiln and purchase the Malyss Root for 200g or CHA/STR check him out of it. Then speak to Andra. She'll ask for ingredients. You should already have Troll Fat and Spider Venom Sac. The Id Moss is near the entrance to the Troll Cave. Grab it and bring it back to Andra. Investigate her house then exit. She will speak to you immediately. Speak with Yenrry after and STR/CHA check him into investigating the altar in the swamp. There are 3 Black Puddings there and it is a really tough fight so be prepared. Once done, use the stone Yenrry gave you on the Altar to reveal a passage below. Enter the passage and confront Andra. She drops the potion and Dabbler's Staff.
For anyone else that gets stuck on this like I did. The Black Puddings won't follow you much past the entrance to the peninsula. So you can equip some ranged weapons and kite them there and back a few times to wear them down.