Natlan Boss Farming Route: Fastest Way to Farm Gluttonous Yumkasaur, Goldflame Qucusaur Tyrant & Secret Source Automaton in 5.5

I went into the Gluttonous Yumkasaur Mountain King fight blind the first time. Died three times before I realized the thing absorbs Phlogiston from the arena to charge its slam attack. Nobody mentioned that in the livestream.

Natlan's world bosses are different from what you're used to. They interact with the region's Phlogiston mechanic in ways that can catch you off guard if you're running the same Liyue-era team you've been using since 2021. After farming the full Obsidian Codex set for Mavuika and building Mualani from the People of the Springs tribe, I figured out what actually works.

Since Natlan launched August 28, 2024 with Version 5.0, and expanded through 5.2 in November and 5.5 in March 2025, the boss roster has grown. Here's what I run and why.

The boss rotation I run every week

I do four bosses per reset: Gluttonous Yumkasaur for Kinich ascension mats (he's from the Scions of the Canopy tribe, Huitztlan), Goldflame Qucusaur Tyrant for Mavuika, the Secret Source Automaton for weapon materials, and the weekly boss Lord of Eroded Primal Fire for talent materials. Takes about 45 minutes if I'm focused.

The Gluttonous Yumkasaur is weak to Dendro reactions, which makes sense since it's basically a giant overgrown version of the Yumkasaurus you can indwell. Bring a Dendro applier and someone who can trigger Burning or Bloom. I use Kinich with a Deepwood Memories set, even at level 70 with scuffed artifacts, because his skill's grappling hook lets you dodge the boss's belly flop without burning stamina. That move has a hitbox wider than it looks. honest.

For the Goldflame Qucusaur Tyrant, the trick nobody told me is that it spawns Phlogiston Wind Tunnels around the arena at 60% HP. If you have a Natlan character in the party, you can use Nightsoul Transmission to instantly swap to them mid-air and glide through the tunnels to avoid the ground-level eruption. Without a Natlan character, you're stuck sprinting to the edges and hoping your shield holds. I learned that one the expensive way.

The Secret Source Automaton in the Collective of Plenty territory (Teteocan) has a Tatankasaurus indwelling point near its arena. Indwell it and charge-attack the boss's shield phase. Two hits break it instead of the usual five or six with normal attacks. The game never tells you this.

What I actually put on my characters

Mavuika wants 4-piece Obsidian Codex. I know people keep arguing about Crimson Witch being comparable and honestly, for Vaporize teams in older regions, maybe it is. But in Natlan specifically, the Codex set gives you 40% increased damage after consuming a Nightsoul point, and Mavuika's whole kit revolves around Nightsoul consumption. I tested both sets against the Qucusaur Tyrant and the Codex cleared it 22 seconds faster on average. That's not a small margin.

The stats I aimed for: ATK% sands, Pyro DMG goblet, Crit Rate circlet. Substat priority is Crit Rate until about 60%, then Crit DMG, then ATK%. Energy Recharge at around 130% is comfortable if you have another Natlan character feeding her Nightsoul Burst procs.

For Mualani, it's Obsidian Codex too but with HP% sands instead of ATK. Her entire damage formula scales off max HP, same way Yelan and Nilou work. She's from the People of the Springs (Meztli) and her surf state replaces normal attacks entirely. Hydro DMG goblet, Crit circlet. Aim for 35k HP minimum at level 90. Her weapon situation is annoying because the Ring of Yaxche craftable is locked behind a world quest chain in the Meztli territory that takes about 3 hours. Worth it though. The HP substat on it is exactly what she needs.

Kinich is the weird one. He wants Scroll of the Hero of Cinder City if nobody else on the team is holding it, because the 4-piece bonus gives a 12% damage bonus to all party members when he triggers a Nightsoul Burst reaction. If someone else has Scroll, put him on Deepwood Memories for the Dendro shred. EM sands, Dendro DMG goblet, Crit Rate circlet. His personal damage is fine but the real value is how he enables Burning and Burgeon for the rest of the team.

Kachina from the Children of Echoes (Nanatzcayan) is free after the first Archon Quest chapter and I genuinely think she's underrated. Her Turbo Twirly drill does Geo damage in an area and she can hold Scroll of the Hero as the trigger for your team buffs. DEF% sands, Geo DMG goblet, Crit Rate circlet. Favonius Lance for team energy.

Artifact farming without losing your mind

The Sanctum of Rainbow Spirits domain drops both Obsidian Codex and Scroll of the Hero. That's not a coincidence. HoYoverse designed it so you can farm for your Natlan DPS and support simultaneously, which is more generous than the Emblem/Shimenawa split from Inazuma where one set was amazing and the other was cope.

My route: teleport to the domain in the Masters of the Night-Wind territory (Mictlan), clear with a team of Mavuika, Furina, Xilonen, and Bennett. Takes about 55 seconds per run. With condensed resin, you get roughly 4-5 artifacts per 40 resin. I tracked 40 runs and got 14 usable pieces with at least two good substats. That's about a 35% hit rate, which is better than the 20% I got farming Emblem for two years.

One thing I figured out too late: don't instantly trash artifacts that roll flat DEF on the first upgrade. The Codex set has such a strong 4-piece effect that even imperfect pieces outperform perfect off-set pieces. I threw away a DEF% sands with double crit substats early on and regretted it when I realized Xilonen actually wants DEF% for her healing.

Resource management nobody talks about

Fragile Resin burns fast in Natlan. Between the weekly boss, three world bosses, and the artifact domain, you'll burn through 300 resin before you know it. I save my Fragile Resin for Sundays when the domain drops both sets and I can binge-farm.

And honestly, don't sleep on the teapot resin. The Transient Resin from Tubby gives you 60 resin per week, which is basically a free condensed run. Took me way too long to start using that. Like, months. I just forgot the teapot existed.

Phlogiston is another thing. You want to max your Statue of the Seven early because each level adds 10 points to your max Phlogiston capacity. At level 10, you have 200 points, which means you can stay in Saurian Indwelling for almost a full minute. It makes a real difference when you're farming bosses back to back and don't want to hunt for crystals between fights.

But the biggest time save is something dumb: teleport waypoints are closer to boss arenas in Natlan than in any other region. Like, the Gluttonous Yumkasaur waypoint is literally 10 steps from the arena entrance. Inazuma bosses made you climb a mountain. Sumeru bosses hid inside hollow trees. Natlan just puts the waypoint right there. I appreciate that.

Team comps for boss farming specifically

For single-target boss fights, I run Mavuika, Citlali, Xilonen, Bennett. Citlali from the Masters of the Night-Wind applies Cryo off-field for Melt reactions, Xilonen shreds RES with her sampler activation, and Bennett is Bennett. The rotation is Bennett burst, Citlali skill into burst, Xilonen skill into two normal attacks to activate her shred, then Mavuika burst into donut combo. The timing is tight but when it lines up, Mavuika's burst initial hit can crack 400k on a Melt crit.

If you don't have Citlali, Rosaria works as a budget replacement. You lose some damage ceiling but the rotation is nearly identical.

For multi-wave boss fights like the Secret Source Automaton that spawns adds, I swap Citlali out for Furina. Furina's salon members handle the small mobs while Mavuika focuses the main body. The team-wide HP drain from Furina is slightly annoying but Bennett's healing circle offsets it if you stand in it consistently.

Don't sleep on Saurian Indwelling during boss fights either. Some arenas have indwellable saurians nearby. The Tepetlisaurus near the Yumkasaur arena lets you burrow underground to avoid the tracking fireballs. I didn't notice it for my first 10 kills. Felt pretty stupid when a commenter pointed it out.

Oh and one more thing. The six Saurian types each have their indwelling spots marked on the minimap with a saurian head icon: Tepetlisaurus (burrow), Yumkasaurus (grapple), Koholasaurus (swim Phlogiston), Qucusaurus (fly wind tunnels), Iktomisaurus (spirit sight), and Tatankasaurus (charge breakable walls). In boss arenas, the icons are easy to miss because the red boss icon overlaps them. Zoom your minimap.