The ingredients for blue goblin armor are goblin armor and blue dye.
To receive goblin armor, kill a few goblins southwest of the Lumbridge cowpen until it drops the goblin armor. You might need to wait sometime for the respawn time of the goblins and other players that kill goblins, too.
To receive blue dye, you will need 25 gp. Go to Falador park and Buy 2 Woad leaves from the farmer to the far west of the park. The head down to Draynor village and give your leaves and remain 5 gp to Aggie (she is in the house northwest of the Wise old man's house ) and she will give you blue dye. Use the blue Dye on the armor and you have blue goblin armor.
You cannot wear blue goblin armor.
The only reason you would need the armor is because you are doing Goblin Village quest.
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