Barrows 1-Prayer Dose guide: Magic/Melee Switch
Requirements: Osmumtan's Fang, Trident, Barrows portal in POH, Ring of Dueling (Ferox Enclave Tele)
Recommended: Imbued God Cape, Occult Necklace, Amulet of Torture/Fury, Brimstone Ring
Other Items: Rune pouch, POH teleport tab, Super Pots, Spade, best offensive melee armor
Order of Brothers: Dharok > Guthan > Kharil > Ahrim > Torag > Verac
Rational: Dharok is the most important to have protect from melee for, while Torag and Verac are the least important. If you run out of prayer at Torag or Verac, your melee gear will be enough to tank the damage. You rarely need to eat any food with this method, and you only ever need one prayer dose in the maze at most.
Other Notes: Switch to Melee for Kharil and Ahrim, then back to mage for Torag and Verac. Enter the maze with melee to kill mosters up to ~86%, and switch back to mage if required for the brother before the chest. Only drink a prayer potion once the brother appears in the maze, and wait until the prayer drain animation before drinking to maximize the dose during the kill. Optionally, use super pots prior to Kharil/Ahrim, and use Piety and Fang special for quick kills.
Costs per KC: 1 Prayer Dose, 1 POH Tele, 1/8th Ring of Dueling, plus Trident spell casts. Usually between 15-30k total.