You can use whatever you want

Weapon: I intend on bringing Rune scimitar for RuneScape gold first visit, and a fetch a cannon for your demon. Shield: Rune Defender(I have like 12 of them) I can substitute it with maybe a rune kiteshield if necessary. I could bring a Bronze-steel halberd too. A few suggestions for my stock would be fine, I do not intend on bringing more than 3-4 prayer pots/super restores, or more than 5 anti-poison, also that I plan on fishing lobsters/swordfish for meals. Also, you may edit whatever in my armor if you'd like. Cheers!

That armor is great for the prayer bonus. As for the weapon, try utilizing the dragon mace or Wolfbane Dagger such as the manual suggests. They give a prayer bonus. I used the manual on the site, and it is good. You can use whatever you want, but prayer gear is the very best. Additionally, since u are using a cannon for the fight, use the exact same prayer armor. Bring a fantastic quantity of prayer potions.

Make sure your Protect From Magic Prayer is turned on and take space from the Demon to be certain it doesn't hit you with melee. Establish your cannon, fire and load it. Now you can wait and in the meantime variety or mage you or it can hide behind the statue in which the demon can not mage you. When needed go reload your cannon, don't forget to flip your prayer back on and make sure you stay clear of buy osrs gold safe its melee attacks! This is by far the simplest way but also the most expensive.