Season 9 of Diablo 4 completely overhauls loot farming with Sins of the Horadrim. It introduces Horadric Strongrooms, Arcana crafting, and a deeper layer of strategy tied to dungeon modifiers, seasonal blessings, and reputation grinds. If you’re wondering how to actually get the materials you need — Arcana, Obducite, Phials, and Jewels — and not waste your time, here’s what matters.
1. Where to Get Arcana
The short answer: Horadric Strongrooms. These mini-dungeons inside Nightmare Dungeons drop Arcana materials but are not auto-loot. Many players are running right past them. Arcana can appear as rare-looking drops in multiple colors (yellow, blue, even legendary), often hidden in plain sight alongside other Diablo 4 items, so check the floor after boss fights or Strongroom clears.
Tip:
- Don’t assume Arcana isn’t dropping. You’re probably missing it visually.
- Recipes, Tomes, and Arcana drops all come from Horadric Caches, especially after the boss fight in Strongrooms.
2. How to Farm Horadric Strongrooms Efficiently
You can run any Nightmare Dungeon and randomly get a Strongroom, or find a Sigil that guarantees one. You’ll find rare loot, Arcana, and sometimes Diablo 4 boost materials to elevate your crafting or XP gain.
When inside:
- Follow the purple glow to the gateway.
- Choose three Pillars to activate: these affect ambushes, enemy behavior, and loot multipliers.
- The goal is to hit six Horadric Attunement before time runs out — this gives you maximum loot.
- Faster clears = earlier boss = faster resets.
You don’t need six Attunement to earn Arcana, but it definitely helps.
3. Obducite, Phials, and Jewels: The Resource Grind
Season 9 is generous with Obducite — especially from:
- Nightmare Dungeons (Torment 1+)
- Strongroom completions
- Dungeon escalations
Phials, however, are a bit trickier:
- Nightmare Dungeon Escalations give 3,000–4,000 per Astaroth kill.
- Specialized Reserves like the Phial Reserve or Gem Reserve dungeons flood you with these materials.
- You’ll need 3,000 Phials to craft one jewel at the Horadric Lapidary.
If you’re running with items, gold boost, or targeting high-density dungeons, your Diablo 4 gold stack can grow just from smart routing.
4. Crafting Horadric Jewels
To craft:
- Visit the Horadric Lapidary near the quest giver.
- You need Phials and Gem Fragments.
Crafted jewels give powerful bonuses, and you can convert excess Phials into Horadric Knowledge (for reputation gain).
5. Strongroom Buffs and Seasonal Strategy
After finishing a Strongroom, you gain a buff:
- More XP, gold, monster favor, or Obducite
- Check the buff before deciding whether to finish the entire dungeon
Seasonal Blessings:
- Invest wisely.
- Urn of Curiosities = double loot from the Purveyor
- Urn of Strongrooms = more Escalation Sigils
- Swap urns depending on what you’re grinding — Arcana, glyphs, or boss loot.
6. Reputation and Knowledge Farming
Forget what the tooltip says — you don’t get rep from dungeon completions. The real rep comes from killing elites:
- Helltides
- Infernal Hordes
- Strongrooms
- The Pit
Don’t waste time farming layer bosses — they give zero reputation.
Convert spare Phials at the Lapidary for extra rep boosts when needed.
7. Are Infernal Hordes Still Worth It?
Yes — but only six-wave runs. You’re after:
- 200 Offering to open large chests
- Temper Reset Scrolls for fixing bad rolls on gear
- Obducite is better farmed through Nightmare dungeons
No need to slog through 10 waves anymore — just in and out.
Final Tips:
- Prioritize Strongroom Sigils
- Never leave loot unchecked — Arcana drops are subtle
- Swap out your Urns based on what you’re farming (Curiosities vs. Strongroom vs. Glyphs)
- Don’t ignore the Horadric Lapidary — it’s your new best friend
