Summary
Diablo 4 Season 15 has a hidden farming route that can reward some of the season's most valuable items, including the Hellfire Torch Mythic Charm, Mythic items, Seals, and other high-end loot.
The process is lengthy at first, but once you understand the route, you can repeatedly farm the materials needed to open the secret boss encounter. The key is reaching Old Tristram, collecting three Prime Evil Splinters, and combining them into Wirt's Lucky Coin. To speed up the farming process, Diablo 4 Gold can help you acquire the necessary materials.
How to Unlock the Secret Tristram Portal
Before you can fight the secret bosses, you need to unlock access to Old Tristram.
Find Deckard Cain's 10 Journals
Return to the Imperial Library, where you encountered Deckard Cain at the beginning of Season 15. To activate the portal to Tristram, you first need to interact with all 10 of Deckard Cain's journals scattered throughout Sanctuary.
When you are close to a journal, a small green circle appears on your minimap. You can use Cain's journal to check your progress and identify which entry you are still missing.
After interacting with all 10 journals, a quest marker appears above the Imperial Library. Return there and speak with Deckard Cain to unlock the portal to Cain's Memory, which leads to Old Tristram.
Once inside Tristram, you can experience original voice lines and interact with familiar characters and quests from the original Diablo.
Farm the Three Prime Evil Splinters
The next requirement is collecting three rare seasonal materials:
Splinter of Terror
Splinter of Destruction
Splinter of Hatred
These Splinters can technically drop anywhere in the world, although the source describes the chance as extremely low. The primary farming method is repeatedly defeating Diablo, Baal, and Mephisto on their Torment 10 versions.
Importantly, the Splinters are not tied to specific bosses. Each of these bosses can drop any of the three Splinters.
Reach Torment 10
Torment 10 unlocks the Hell difficulty for these encounters. However, the source recommends reaching Torment 12 before seriously farming the Splinters because the bosses can be extremely difficult.
A strong build and high damage output are especially important if you want to complete these runs quickly. The faster you kill the boss, the more attempts you can complete per hour.
Farm Baal for Fast Splinter Runs
Among the three bosses, the source recommends Baal as the practical farming target because the route to him can be completed quickly.
Navigate the Baal Dungeon Efficiently
There are several useful navigation patterns that can help shorten the trip to Baal.
If your entrance appears in the bottom-left and points toward the right, the area summit should generally be toward the upper-right or above. If the entrance is on the right, check toward the upper-left or above.
Learning these patterns lets you quickly identify the correct direction instead of exploring the entire dungeon.
Movement speed also makes a significant difference when repeatedly farming the same boss.
Collect Rewards Along the Way
Before reaching Baal, you can encounter three Ancients at the Ariat Summit. According to the source, these enemies provide 200 seasonal reputation each and can drop Legendary Seals, Greater Affix items, and valuable gems.
This makes the run useful even when Baal fails to drop a Splinter.
After clearing the enemy waves before Baal, use the shortcuts available in the area to reduce the amount of running required. Once you reach the boss, defeat him as quickly as possible and reset the dungeon.
The source reports taking roughly 10 attempts to obtain both the Splinter of Terror and Splinter of Destruction, while continuing to work toward the Splinter of Hatred.
Reset and Repeat the Boss Farm
After killing Baal, leave the dungeon and use the map's Reset Dungeon option to begin another run.
The advantage of this method is that every run can provide more than just a chance at a Splinter. The boss can also drop Mythic items and other valuable gear.
The source also reports earning Forgotten Souls, Horadric Dust, Seals, Charms, and gems during these farming sessions. As a result, repeated Baal runs can simultaneously build up several different crafting and progression resources.
Combine the Splinters Into Wirt's Lucky Coin
Once you have collected all three Prime Evil Splinters, take them to the Horadric Cube.
Place the Splinter of Terror, Splinter of Destruction, and Splinter of Hatred into the Cube and transmute them. The three materials are converted into Wirt's Lucky Coin.
This coin is the item required to activate the secret boss portal in Old Tristram.
Open the Secret Mythic Portal
Return to Old Tristram and take Wirt's Lucky Coin to the Tristram fountain.
Interact with the fountain while carrying the coin. A large red portal opens, giving you access to the secret boss encounter.
Make sure your character is strong enough before entering. This is intended to be a high-end encounter, and the entire farming process becomes much more efficient when you can defeat the bosses quickly.
Defeat the Secret Bosses
Enter the portal and fight the bosses inside the special Tristram encounter.
The source describes this as a particularly rewarding pinnacle encounter, with the potential to drop multiple Mythic items alongside special seasonal rewards.
After defeating the bosses, collect all the loot carefully. The rewards shown include Mythics, a Mythic Charm, Seals, and the Hellfire Torch.
Why the Hellfire Torch Is So Valuable
The Hellfire Torch stands out because of its unusually powerful bonuses.
According to the source, it provides:
+4 ranks to all skills
Resistance to all elements
All Stats
The ability to equip another Unique Charm
Set-piece functionality
The ability to equip an additional Unique Charm is particularly important for build customization. Because the Hellfire Torch counts as a set piece, it can also contribute toward the requirements of the Nameless set.
This opens up combinations involving the Hellfire Torch, multiple Unique Charms, and different numbers of Nameless set pieces.
Consider the Mythic Seal
The source also mentions a Mythic Seal that can reduce the number of set pieces required, potentially allowing even more flexibility when combining the Hellfire Torch with Unique Charms.
The exact optimal combination will depend on your build, but the Torch's ability to function both as a powerful charm and as a set piece gives it substantial itemization potential.
Repeat the Farm With Friends
Once you understand the process, the secret portal farm can be repeated by farming the three Splinters again and converting them into another Wirt's Lucky Coin.
The source also notes that players may be able to share the portal with friends, potentially allowing groups to complete the encounter together.
For players already capable of clearing Torment 10–12 efficiently, the farm offers several rewards at once: Splinters for the secret portal, Mythic items, crafting materials, Seals, Charms, gems, and other valuable drops. To maximize your efficiency during these runs, buy Diablo 4 Gold and stock up on gear.
The complete loop is therefore simple once unlocked:
Complete Cain's journal quest → Enter Old Tristram → Farm three Prime Evil Splinters → Combine them into Wirt's Lucky Coin → Use the coin at the Tristram fountain → Enter the secret portal → Defeat the bosses → Loot the Hellfire Torch and other rewards.
