The best way to kill Grotworms is with a crossbow since they are weak to bolt attacks. The best weapons to use are: • Blightbound Crossbow • Ascension Crossbow • Chaotic Crossbow • Armadyl Crossbow • Dragon Crossbow • Rune Crossbow If you have a low ranged level, then you can use magic or melee to kill the worms. However, you’ll do significantly less damage, and kills will take longer to finish.