[3.0] Scorching Ray Tri-Totem w/ RF

Ancestral Bond: Probably the most important node to get, this, while causing you to deal no damage through RF, allows you to have 3 Scorching Ray totems when combined with Soul Mantle.
Unwavering Stance: The only other relevant keystone for this build. While it isn't necessary, it can be nice to keep yourself from being stun-locked. Can be replaced with Kaom's Roots if you have the currency and resists to spare, or just ignored if you feel your defenses are good enough.

A Rise of the Pheonix is one of the two most important items of this build, and is quite cheap at a pretty constant 1c. Just about required for sustaining RF, due to the 8% increased maximum fire resistance.

Soul Mantle is another quite important item, allowing us to replace Spell Totem with another gem due to the "Socketed Gems are Supported by level 20 Spell Totem", as well as giving us 50% more damage from having a third totem. There is the downside of being cursed whenever a totem dies or despawns, but there are ways to get around this. Generally considered useless by the community, and is therefore usually only a few chaos.

Twin Kikazarus give us a massive amount of health regeneration to help deal with and surpass RF, but most importantly, they reduce the effect of the curses we will constantly be recieving from the Soul Mantle. Having just one Kikazaru will work fine as well, if you, like me, don't have the currency to replace the loss of resistances from not having a real ring, but you will have to deal with much stronger curses. Very cheap, usually only 1c.

Doon Cuebiyari is a very nice weapon for this build, due to the 1% increased damage per 8 Strength it provides in the main hand. Due to this build being for a Marauder, getting a ton of strength is easy, and this sceptre provides a very nice increase to your total damage because of it. The level 30 Iron Will it provides is unfortunately largely wasted, although you can stick a Searing Bond setup in it for a little extra damage. Another very cheap item, only ever a chaos or two.

A very nice helmet for this build, being one of the few sources of increased fire damage. While it doesn't provide much in the way of defenses, the offensive power it provides is a large bonus due to the small amounts of increased damage on the tree. One of the cheapest items in the build, costing as much as an alch.

The 2% life regen from the Primal Skull Talisman is very helpful, giving even more regeneration to counter the high degen from RF. The desired mods for the item are quite standard though, just life and resists, and stats if you need them. For any league that doesn't have access to Talismans (so far anything that isn't Standard), any amulet will do here.

For the rest of the items, the standard life, resists, and movespeed are all that are necessary, with the occasional bit of stats as needed. There are no specific unique items that are of great use for this build.

Scorching Ray - Spell Totem (from chest) - Burning Damage - Efficacy - Elemental Focus - Controlled Destruction - Swift Affliction
Your main damage setup, placed in your chest for the pseudo 7-link. This should be the only active skill casting off mana, due to the low mana and high health regeneration of this build.

Searing Bond - Burning Damage - Blood Magic
A bit of extra damage for boss fights, or if you feel you need the extra clearspeed. Put it in a Doon Cuebiyari for the additional level 30 Iron Will link.

Righteous Fire - Vitality - Purity of Fire - Flammability
These four are pretty self-explanatory. Righteous Fire for the more spell damage, Vitality to counter the RF, Purity of Fire for the extra max fire resistance, and Flammability to decrease enemy resistances.

Shield Charge - Faster Attacks - Blood Magic - Fortify
The only movement skill you can use. Faster Attacks to be usable more often, Blood Magic so you can use it whenever you need it, and Fortify to help mitigate damage taken.

Help Oak for the 1% regeneration, two passive points won't net you much beyond some stat points

Major God: Arakaali, for the 5% reduced damage over time taken. Not particularly important, and can be switched out without any issue.

Minor God: Any. None of the gods give any particularly good bonuses for this build.