One of the main mechanics of Diablo 4 Season 15 lets you wield a fragment of Diablo's, Baal's, or Mephisto's power. After progressing through the seasonal questline, your character obtains all three Splinters of Evil, chooses one to bear, and begins leveling a separate reputation track. As you gain ranks, additional upgrades for that Prime Evil Power gradually unlock.
Don't spend half an hour staring at the first choice and wondering which of the three buttons to press. The decision isn't permanent. Later, you can switch between the Splinter of Terror, Splinter of Destruction, and Splinter of Hatred, and any reputation you've already earned remains intact. In fact, it makes sense to level all three tracks over the course of the season because they improve very different activities.Image unavailableIn this guide, we'll explain how to unlock Diablo's, Baal's, and Mephisto's powers, where to earn reputation, which ranks unlock every upgrade, and what each of the three Splinters actually does.
How to Unlock the Prime Evil Powers
The system is tied to the main Season of Hell's Legacy questline. As you progress, Deckard Cain sends your character into memories of the three Prime Evils. You'll first confront Baal, then Mephisto, and finally Diablo himself.The story encounters unlock at later Seasonal Ranks. Baal becomes available at Rank 5, Mephisto at Rank 6, and Diablo at Rank 7. If your character is clearly too weak for the next challenge, don't try to brute-force the boss at any cost. Level up, improve your build, and come back later. The seasonal powers aren't going anywhere.After completing the entire chain and defeating all three enemies, you'll have:
Splinter of Terror - Diablo's power;
Splinter of Destruction - Baal's power;
Splinter of Hatred - Mephisto's power.
The game then asks you to choose one. That Splinter becomes active, grants its Iconic Power, and opens its own reputation track.
How Splinters of Evil Work
You cannot wield all three Prime Evil Powers at the same time. Your character bears only one Splinter, and the associated ability triggers automatically during combat. There is no separate button for it on the action bar. Keep playing your build normally, and Diablo, Baal, or Mephisto will periodically make their presence known on their own.Image unavailableThe Splinter of Terror unleashes Fire and provides additional bonuses for Helltide and Infernal Hordes. The Splinter of Destruction deals Cold damage and is tied to the Undercity and Lair Bosses. The Splinter of Hatred summons ghosts that deal Physical damage, while its activity bonuses focus on The Pit and Nightmare Dungeons.
All three tracks also interact with the Tree of Whispers.
There is one catch. While bearing a specific Splinter, your character becomes more vulnerable to the corresponding Prime Evil. Take Diablo's power and Diablo himself becomes more dangerous. It's easy to forget during normal farming, but before returning to fight that boss again, it's worth remembering why some attacks suddenly seem to hit much harder than expected.
How to Upgrade Splinters of Evil
Each of the three Splinters has its own 24-rank reputation track. You gain reputation by entering Waking Nightmares and slaying remnants of evils past. Additional rewards are also tied to the activities enhanced by your chosen Splinter.There is one simple detail that can waste a lot of time if you miss it: progress is earned for the active track. If you're currently bearing the Splinter of Terror, you're leveling Diablo. Want to work on Mephisto instead? Switch to the Splinter of Hatred first.The base Iconic Power is available immediately at Rank 1, while the six major upgrades unlock at:
Rank 2 - 350 Reputation;
Rank 6 - 1,300 Reputation;
Rank 10 - 5,150 Reputation;
Rank 16 - 13,100 Reputation;
Rank 21 - 17,400 Reputation;
Rank 24 - 20,000 Reputation.
The ranks between them aren't empty either. At Ranks 4, 5, 8, 12, 14, 18, 20, and 22, you receive special War Plan Activity Modifiers. Depending on the active Splinter, they enhance Helltide, the Undercity, The Pit, and other endgame activities.Image unavailableSo a fully upgraded Splinter isn't just seven combat effects. You also unlock eight seasonal modifiers for endgame content.
All Diablo Powers - Splinter of Terror
The Splinter of Terror is a natural fit for players who spend a lot of time in Helltide and Infernal Hordes. Diablo's base power deals Fire damage, while later upgrades add Primary Resource generation, Vulnerable, and damage based on the enemy's Maximum Life.
Rank 1 - Flames of Metus
This is Diablo's base power. Periodically, lines of flame erupt from your character, dealing initial Fire damage and then burning affected enemies for several seconds. You don't need to build a special rotation around it. Flames of Metus triggers automatically and simply adds another source of damage on top of your normal skills.
Rank 2 - Flaring Cinders
During Helltide, Flames of Metus begins spawning additional Aberrant Cinders. The first upgrade is fairly specialized, but it unlocks after only 350 Reputation. If you're actively farming Helltide, you'll feel the benefit almost immediately.
Rank 6 - Pounding Heart
Every trigger of the base power generates 50 Primary Resource. This is the point where the Splinter of Terror starts helping almost everywhere rather than only inside a specific activity. Barbarians gain Fury, Necromancers gain Essence, Sorcerers gain Mana, and so on. Builds that constantly burn through their resource will certainly appreciate the free refill.Image unavailable
Rank 10 - Primeval Essence
During Infernal Hordes, Flames of Metus begins spawning additional Aether. If you regularly run Hordes for the final chests, this effectively turns the seasonal power into extra loot. Again, you don't need to activate anything manually. Just keep killing enemies.
Rank 16 - Dread Presence
The flames now Slow affected enemies by 30% and make them Vulnerable. We'd consider this one of the major turning points of the track. Before Rank 16, Diablo mostly adds damage and resources. From this point onward, the power also automatically applies a useful debuff to almost everything caught by the flames.
Rank 21 - Consuming Blaze
The first time Flames of Metus hits an enemy, it deals additional damage equal to 20% of that enemy's Maximum Life over four seconds. This damage cannot be increased by other modifiers. Even so, against high-health Elites and Bosses, the effect is much more interesting than another small increase to ordinary damage.
Rank 24 - Rapture of Fear
Killing enemies can fill your character with Rapture of Fear for five seconds. While it is active, Flames of Metus triggers dramatically more often.This is the final upgrade and one of the reasons the fully leveled Diablo track feels much more entertaining than its starting version. In large packs, the bursts can begin firing one after another, especially if your build already deletes normal enemies quickly.
Diablo War Plan Modifiers
Alongside the power itself, the Splinter of Terror improves Helltide, Infernal Hordes, and the Tree of Whispers.The bonuses are:
Rank 4 - Demonic Rats in Helltide are always Elite and drop more Aberrant Cinders;
Rank 5 - a Doomsayer appears at the start of every Infernal Hordes wave;
Rank 8 - Corrupted Roots appear more often in Whisper Caches;
Rank 12 - Hellwyrms have a chance to make you smell of Fresh Meat, potentially drawing out The Butcher;
Rank 14 - Impending Doom in Infernal Hordes can trigger with 30 seconds remaining in the wave;
Rank 18 - Shrine effects during Helltide last 15 seconds longer and grant +50% Movement Speed;
Rank 20 - the Council Coffers chest in Infernal Hordes costs only 1 Aether;
Rank 22 - Corrupted Roots gain another +1 Monster Power, while using them in Helltide grants a large amount of Aberrant Cinders.
Image unavailableIf your usual Diablo evening consists of Helltide, a couple of Infernal Hordes runs, and then another Helltide, the Splinter of Terror practically asks to be equipped.
All Baal Powers - Splinter of Destruction
The Splinter of Destruction revolves around Cold damage and is especially useful for players farming the Undercity and Lair Bosses. Compared with Diablo's track, it focuses less on regular seasonal currency and more on additional loot.
Rank 1 - Ice of Excidium
Baal's power periodically creates a large ice blast around your character. The explosion then fires additional smaller projectiles that damage nearby enemies. The main burst hits much harder than the smaller shards, but in dense groups those projectiles still help spread damage across several targets.
Rank 2 - Siege Engine
Inside the Undercity, Ice of Excidium has a chance to grant additional Attunement. If you're currently leveling or collecting rewards through the Undercity, Baal's first upgrade is more useful than it may look on paper.
Rank 6 - Cold Blood
Each ice blast generates 50 Primary Resource.Image unavailableThis follows the same basic pattern as the Rank 6 upgrade on the other Splinters, and that's a good thing. Its usefulness isn't tied to a specific class or activity.
Rank 10 - Grisly Trophies
Bosses hit by Ice of Excidium have a 30% chance to drop an additional Boss Trophy when killed. This is where Baal becomes especially attractive for players already farming Lair Bosses repeatedly. An extra trophy means another opportunity to continue the boss-farming chain without making a separate trip for materials.
Rank 16 - Seizing Frost
The main blast Chills enemies by 10% and makes them Vulnerable for five seconds. The smaller ice projectiles also apply Chill, but at half the amount.The result is a useful combination of Crowd Control and Vulnerable that doesn't require rebuilding your character around the Splinter itself.
Rank 21 - Shattered Flesh
The first hit from Ice of Excidium against each enemy deals additional damage equal to 20% of its Maximum Life over four seconds. As with Diablo's equivalent upgrade, the extra percentage cannot be increased by other multipliers. Against targets with enormous health pools, however, the effect remains particularly noticeable.
Rank 24 - Thrill of Ruin
Killing enemies can fill your character with Thrill of Ruin for five seconds, dramatically increasing the number of Ice of Excidium blasts you unleash.At maximum rank, Baal's power becomes far more aggressive. In packs where enemies are constantly dying, the ice bursts can fire with very little downtime.
Baal War Plan Modifiers
The main activities here are the Undercity, Lair Bosses, and the Tree of Whispers.
Rank 4 - you gain 50% more Experience Orbs in the Undercity, while Monster Power is increased by another +1;
Rank 5 - Whisper Ambushes trigger more often;
Rank 8 - an Invasion Portal appears at the start of every Undercity floor;
Rank 12 - Last Gasp begins granting its doubled bonus time at 15 seconds remaining instead of 5;
Rank 14 - Lair Bosses drop additional Runes;
Rank 18 - the chance for a Nemesis Lair Portal to appear is increased;
Rank 20 - Boss Hoard chests grant an additional 3 Unique items for any class;
Rank 22 - bosses from Whisper Ambushes gain +2 Monster Power and drop improved Lair Keys.
If you're currently collecting Unique items or constantly running the boss ladder, Baal is well worth trying. After Ranks 10 and 20 in particular, the track begins saving you farming time directly.Image unavailable
All Mephisto Powers - Splinter of Hatred
The Splinter of Hatred deals Physical damage and specializes in Nightmare Dungeons and The Pit. This track becomes especially interesting for an established character whose main goals are leveling Glyphs, collecting Artificer's Stones, and pushing higher tiers of endgame content.
Rank 1 - Ghosts of Odium
Mephisto's power periodically unleashes Ghosts of Odium, which attack nearby enemies for Physical damage. Everything happens automatically. If spirits suddenly appear during your normal rotation, it isn't some new effect from your build. It's the active Splinter of Hatred.
Rank 2 - Undying Rage
Inside Nightmare Dungeons, Ghosts of Odium trigger 50% more often and deal 200% increased damage. Unlike the first upgrades for Diablo and Baal, this is a very direct combat bonus. The limitation is that it only applies inside Nightmare Dungeons.
Rank 6 - Flush of Bile
Ghosts of Odium generate 50 Primary Resource whenever they trigger. If your build constantly burns through Mana, Fury, Essence, or another Primary Resource, Rank 6 noticeably smooths out the gaps between attacks.
Rank 10 - Death Collector
In The Pit, enemies damaged by Ghosts of Odium have a chance to drop additional Progress Orbs when they die. This is a genuinely strong bonus for the activity. The progress bar fills faster, meaning less time spent hunting down the last few percent before the boss portal opens.
Rank 16 - Strangling Grip
The ghosts make enemies Vulnerable for five seconds and have a 15% chance to Immobilize them for two seconds. Crowd Control obviously isn't going to perform miracles against bosses, but in large packs, occasionally pinning an enemy in place can save you unnecessary trouble.
Rank 21 - Vengeful Soul
The first hit from Ghosts of Odium against an enemy deals additional damage equal to 20% of the target's Maximum Life over four seconds. This damage cannot be increased. At Rank 21, all three Splinters line up around the same core idea: each receives its own version of the same Maximum Life-based damage effect.Image unavailable
Rank 24 - Fever of Malice
Killing enemies can enrage your character with Fever of Malice for five seconds, dramatically increasing the number of Ghosts of Odium unleashed.This is the final upgrade for the Splinter of Hatred and the last major reward for reaching the full 20,000 Reputation.
Mephisto War Plan Modifiers
Mephisto's track is built around Nightmare Dungeons, The Pit, and late-game character progression.
Rank 4 - there is a 50% chance for a second War's Bounty Chest to appear at the end of a Nightmare Dungeon;
Rank 5 - completing Whispers also grants Experience Orbs;
Rank 8 - Nightmare Dungeon bosses have a higher chance to revive and gain another +1 Monster Power;
Rank 12 - killing an Elite enemy in a Nightmare Dungeon has a chance to open a Horadric Shrine;
Rank 14 - you gain 50% more Artificer's Stones in The Pit;
Rank 18 - you gain one additional Glyph upgrade attempt for every five minutes remaining;
Rank 20 - Glyph upgrade success chance is calculated as though you had completed a Pit tier 10 levels higher;
Rank 22 - if a Tree of Whispers Cache would grant a Resplendent Spark, you receive two instead of one.
Late in the season, the Splinter of Hatred starts looking particularly attractive. Artificer's Stones, Glyph upgrades, and Resplendent Sparks aren't just bonuses that make the result screen look nicer. They directly push an already developed build further.
Which Splinter of Evil Should You Choose First?
We wouldn't choose based on Diablo being the coolest character, therefore Diablo. Look at what you're actually doing right now.If your character is still actively farming Helltide and Infernal Hordes, the Splinter of Terror fits that route well. Need Unique items, Runes, and constant Lair Boss runs? Try the Splinter of Destruction. Already focused on The Pit, Glyphs, and late endgame progression? Switch to the Splinter of Hatred.The three tracks are also deliberately designed so that several combat bonuses are broadly comparable. At Rank 6, all three generate 50 Primary Resource. At Rank 16, all three begin applying Vulnerable. At Rank 21, each adds damage equal to 20% of the target's Maximum Life. At Rank 24, all three dramatically increase the frequency of their base power for a short period after kills.
That means the activity bonuses matter far more than the difference between fire, ice, and ghosts.
How to Switch Between Diablo, Baal, and Mephisto
Your first choice does not lock your character to one Prime Evil for the rest of the season. To switch, you need to obtain another Splinter of Evil of the desired type and use it. Additional Splinters drop from repeatable Waking Nightmares. At Torment X and above, the hardest versions of the Prime Evil encounters become available and can be repeated for rewards. Splinters can also appear among seasonal reputation rewards.Image unavailableUsing a new Splinter replaces the one you're currently bearing, and the consumable itself is spent. So if you frequently switch between Baal and Mephisto, don't throw away duplicates. You'll need them again.
Most importantly: an upgraded reputation track does not reset. You can raise Diablo to Rank 16, switch to Mephisto and take him to Rank 24, then return to Diablo several days later exactly where you left off.
How to Fully Upgrade All Three Splinters
Fully upgrading one Prime Evil Power requires reaching Rank 24 and 20,000 Reputation. You must do this separately for Diablo, Baal, and Mephisto.We don't recommend switching powers every half hour. Start with the track that best matches your current farming route and take it to at least Rank 21. Better yet, finish Rank 24 immediately. After everything required to reach that point, the final few thousand Reputation no longer look particularly frightening.Then farm another Splinter and move to the next track. This way, you always have at least one power operating close to maximum strength instead of three half-finished options at once.If your only goal is Reputation, prioritize short Waking Nightmares you already know well. Once your character can comfortably clear the enemies inside, several quick runs usually feel better than one long dungeon where half the time is spent simply moving between fights.
What to Do With Extra Splinters of Evil
Don't throw them away even after fully upgrading all three reputation tracks. First, each Splinter is consumed when you switch powers, so having spares is always useful.Image unavailableSecond, one Splinter of Terror, one Splinter of Destruction, and one Splinter of Hatred are required for one of Season 15's major hidden questlines. Combine all three in the Horadric Cube to create Wirt's Lucky Coins.From there, you'll need Tristram and a secret encounter against all three Prime Evils. We've covered the full route, including crafting the coins and obtaining the Mythic Charm, in our Hellfire Torch guide.And if Tristram itself still isn't unlocked, you'll first need to investigate Deckard's memories. Every location is listed in our guide to all 10 Deckard's Journals and unlocking Tristram.Ultimately, there isn't much point in trying to identify one single best power for the entire season. Diablo is more convenient for Helltide and Infernal Hordes, Baal is more useful for Lair Boss and Undercity farming, and Mephisto shines in The Pit and Nightmare Dungeons.Level whichever track helps your current goals. When those priorities change, pull out another Splinter and switch.
