General note: This is not a budget build, I spent ~1 mirror overall between all gear, gems, supports, etc. 

Build Showcase (200% Deli T16 Breach / Ritual / Mapping): https://youtu.be/d9IeHohlaxs

POB: https://pobb.in/_BbyhgkHeScZ  Notes – POB numbers show damage per explosion, which shotgun. Additionally I included the Verglas buff in POB custom configs as it is currently not supported (gotta pump those POB warrior numbers, as is tradition) but feel free to delete that line if you would like to see a non-buffed damage total. I will say that in general t16 200% deli mapping I never felt like I had to have Verglas up, everything blew up either way. The new POB version that dropped today added support for Sinister Jewel Sockets, would recommend updating to that if you’re looking at the POB seriously.

Like many of you I saw the Stormcaller Arrow Spirit Walker build posted by u/Practical-Energy1346 last week (https://www.reddit.com/r/pathofexile2builds/comments/1ufgeci/stormcaller_arrow_spirit_walker_explodes_the/). I thought this build looked super interesting, but as he mentioned in his video he wasn't planning to push it any further or try to min-max it. While it looked neat, it seemed some of the requirements may hamper it a bit in the endgame and thought the build could be pushed much further with more currency by going with Gemling Legionnaire, due to all the synergistic alternate qualities Gemling gets access to.

For those that may have missed the original build, the premise of it is that while the projectiles from Stormcaller Arrow cannot shotgun, the follow-up lightning bolts are treated as secondary explosions and can shotgun. To take advantage of this, the build stacks projectile count and AoE in order to maximize explosion overlaps. In the original build this stacking is done in several ways, through a conditional periodic buff granted by the SpiritWalker ascendency, the unique Lioneye's Glare bow, Olroths Conviction support for additional +Projectile empowered attacks, and using the Fork support + 100% chance to create an additional projectile to convert every originally fired projectile into 3. The downside of this setup is being shoehorned into using Lioneye's Glare which is a super low DPS bow, as well as needing to invest a bunch of passives + affix slots into reducing your Presence area (to enable Lioneye's Glare repeats). Additionally, as Dr3adful mentions in his build guide video, there really aren't 4 ascendency nodes that really fully synergize with the build on Spirit Walker.

The core of the original build is the periodic buff granted by Spirit Walker which grants +6 projectiles fired on your next attack (and 200% increased projectile speed -> 200% increased damage). I had looked over Gemling's alternate qualities a few times during this league and knew that Stormcaller Arrow granted +Projectiles. With some baseline quality stacking I saw it was possible to get a permanent (non-conditional) +4 projectiles on every attack at the 40% quality breakpoint on Stormcaller Arrow. After seeing this I started looking for other interactions with alternate qualities and found quite a few that synergized quite well with the build to juice its damage numbers:

 - Frost Wall: The build uses Frost Wall for single targets / bosses to proc the fork interaction and generate a huge number of explosions in a small area. Essentially you pop a Frost Wall, shoot your arrows into it, arrows fork inside of Frost Wall and then explode. With Gemling quality stacking paired with the Ice Walls passive node we can get some crazy life totals on Frost Wall (I'm currently sitting on 488k life). With Verglas support this converts to 244% of all damage as extra cold, a ridiculous 3.5x damage multiplier off a single support gem.

- Barrage: The original build opted not to use barrage due to its built-in limitations around needing Frenzy charges to really take advantage of it. However, the Gemling alternate quality grants chance not to consume charges, meaning that with a bit more investment we can perpetually maintain our charges and then can spam out empowered Barrage casts every few seconds. My current build has a 99% chance not to consume Frenzy charges with a 30 second Frenzy charge lifetime. This has a 20% chance to provide double benefits, meaning that with 5 frenzy charges we have a 20% chance to repeat our skill a ridiculous 12 times, which is gigantic overkill for everything in the game but is pretty hilarious when it happens.

- Tornado Shot: The alternate quality on this raises the cap for Tornados, with +4 Tornados at 40% quality, meaning you can have up to 5 active Tornados at once, each of which shoots out 3 projectiles for each projectile that hits them. Additionally, due to our quality stacking we almost totally negate the inherent “35% Less Damage” downside of copied projectiles from Tornado Shot, with the quality granting +33% More Damage for a total net of 2% Less Damage on copied projectiles. Basically, just another way to generate a ton more projectiles which can then fork and further shotgun.

- Berserk: If we’re able to generate rage (I’m accomplishing via an Absent Amulet with Eternal Rage) stacking quality can give some ridiculous value. Currently the quality + alternate quality from Berserk is granting me +22% increased rage effect and +17 maximum rage

- Mana Remnants: Quality stacking gives us a ton more mana as well as a large amount of mana regen. This combined with the natural mana regen Gemling gets through Virtuous Motes meant that after taking a single mana cost efficiency notable (via a Megalomaniac jewel) I haven’t had any mana sustain issues at any point while mapping or bossing.

Putting all the above together, we end up with a huge amount of damage and projectiles that are consistently available to us. With this, the Lioneye’s Glare bow didn’t really provide much, was super low DPS (~300 with max rolls), and meant that we would need to spend passive points to cheese our Presence AoE. Due to these reasons, I dropped this bow entirely for a more traditional high-crit Obliterator bow with an “Increased Elemental Damage with Attacks” prefix. The rest of the build’s offenses come from the expected bottom-right side crit and damage nodes on the tree, as well as AoE stacking where possible. Between gem level boosts (which boost base AoE) and increased AoE from the tree we end up with a 4-meter radius on lightning bolt explosions, allowing for an extremely consistent shotgunning pattern.

Firing an additional projectile is an important concept in the build as its essentially a 1.5x more damage multiplier. This is accomplished in the original build via the Split Shot and Forking Projectiles nodes on the tree. However, they really aren’t very convenient to path to and end up taking a minimum of 8 points to pick up, with it being likely you end up using 12 to also path to the nearby nodes for additional projectile chance. Instead, I found that this node is readily available on gloves that can roll Marksman Modifiers with a roll of up to 100%, meaning that portion of the tree can be dropped entirely. Alternatively, you can socket in a Controlled Metamorphosis jewel in the nearby jewel socket below which would allow you to pick up those points without travelling, as well as a couple other relatively high-value notables. At the end of the day you’re still trading several passive points for a single affix line on gloves though, so would definitely recommend just going the gloves route. Additionally, these gloves can also roll cool stuff like Surpassing Chance to Fire an Additional Projectile, or +levels of all Projectile Skills, so you can get quite a bit of value out of the properly rolled gloves.

As far as defenses go – the original build utilized Ward Stacking via Runeforged Brass Dome. In my iteration I instead went for a more traditional CI-based Evasion + Deflect package, primarily due to Gemling’s Virtuous Barrier which allows for double-dipping the benefits of Dexterity Motes – benefits which are lost if you get hit. My current iteration of the build gives me 85% increased Evasion and ES from the ascendency, which is further complemented with Charge Regulation to give the build 80% evade chance, 95% deflect chance, and up to 6k ES (Herald of Thunder + Rite of Passage with Spirit of the Wolf for Endurance Charge generation). I played this build from 92-96 pretty much exclusively doing 200% deli (or pathing to more mirrors) and did not get close to dying at any point.

With offense and defense sorted out, I also put a decent amount of emphasis on QoL. One of the main downsides of Stormcaller Arrow is the 1.5 second detonation delay from firing, which was definitely annoying while playing. To address this, I swapped out Vorana’s Siege (which was giving AoE and single target damage) for Compressed Duration 2. Net effect of this was going from 4.4m radius to 4m radius, but in return taking our detonation delay to under 1 second. The damage and AoE change was not noticeable for me – everything on the screen still explodes basically instantly, but the smoothness improvement was noticeable. Additionally, Gemling’s Gem Studded ascendency notable grants 40% less movement speed penalty when firing, and I’m running a defensive / movement speed Mageblood to further improve mobility.

Offense and Defense are shored up with a variety of different spirit reservation skills, which necessitates either a spirit chest or Morior Invictus with Spirit per Socket Filled.  Spirit Skills I’m currently running:

- Eternal Rage (free via amulet): Rage generation

- Berserk: More rage, rage effect

- Herald of Thunder: Damage + Endurance Charge generation with Spirit of the Wolf Rite of Passage

- Combat Frenzy: Frenzy Charge generation

- Charge Regulation: Skill speed (Frenzy) and more ES / Evasion (Endurance)

- Mana Remnants: Mana sustain

- Wind Dancer: Evasion

- Ghost Dance: ES

I found that I needed 201 spirit to run all of the above with my current setup.

To run all of the skills I did find that I needed to anoint Augmented Flesh (+2 skill slots), but I don’t think any two skills would be worth dropping to allow for anointing anything else. The only other thing that may be somewhat worthwhile would be the extra Sinister Jewel Socket. Additionally, between the gear and skills I needed high Int / Str / Dex. The only way I found to fit all the necessary stats into the build was by running a Legacy of Greymake in my helm, which grants +50 to all attributes. This means that the helm must be an exceptional base so that you can socket in both this plus a Raven-touched shard to allow for a second anoint (Remember – the helm CANNOT be corrupted or you can’t anoint it).

Anyhow, that’s pretty much everything, here is where I’m getting quality from:

- 20-23% base (break-point dependent)

- 6% from ascendency

- 5% from desecrated suffix on amulet

- 5% from Paragon anoint

- 5% from Fox Idol in body armor

This gives a global quality boost of 21% on top of the skill’s baseline 20% quality.

Chance not to consume comes from:

- 44% from quality – 23 + 21 global boosts above

- 25% from Perpetual Charge support

- 15% from suffix on boots

- 10% from The Fabled Stag (via Megalomaniac to save 5 passive points)

- 5% from Dialla’s Desire

For a total of 99% chance not to consume charges