Infinity

Infinity is the most impactful mercenary runeword in Diablo 2 Resurrected, created with Ber + Mal + Ber + Ist in 4-socket polearms and spears (spears added in Patch 2.4). The Level 12 Conviction Aura When Equipped makes this runeword essential for nearly every elemental damage build, as it breaks enemy immunities and shreds resistances.

Conviction Aura Mechanics

The Conviction aura reduces enemy fire, cold, and lightning resistances by -85% and lowers defense by 83% within a 13.3-yard radius. Against non-immune enemies, this massive resistance reduction dramatically amplifies elemental damage. Against immune monsters (100%+ resistance), Conviction functions at one-fifth effectiveness (-17%), meaning it can only break immunities for monsters with 116% resistance or lower.

Lightning immunities are the easiest to break—most lightning-immune monsters have 105-115% resistance. Fire immunities are more challenging, with many unbreakable fire immunes in key farming areas like Chaos Sanctuary and Throne of Destruction. Cold immunities are hardest to break, as most cold-immune monsters exceed 120% resistance, making Infinity ineffective for cold builds (which already have Cold Mastery for resistance reduction).

Best Uses & Builds

Mercenary-Wielded Infinity

Infinity is best-in-slot for Act 2 mercenaries supporting Lightning Sorceresses, Lightning Javazons, and Lightning Trapsin builds. These builds benefit from the immunity-breaking Conviction aura while maintaining full offensive gear loadouts. Fire-based builds (Fire Sorceresses, Fire Druids) gain significant value despite many unbreakable fire immunes, as the resistance shred against non-immune enemies and bosses is devastating.

The -(45-55)% To Enemy Lightning Resistance only applies to the wielder—your mercenary benefits from this bonus, but your character does not. However, the Conviction aura affects all nearby enemies for everyone in range, including party members.

Self-Wielded Nova Sorceress

Since Patch 2.4 enabled Infinity in spears, Nova Sorceresses can self-wield Infinity in a two-handed scythe or spear base. This allows the Sorceress to benefit from both the Conviction aura AND the -(45-55)% To Enemy Lightning Resistance modifier, significantly amplifying Nova damage. Self-wielding Infinity frees the mercenary to equip Insight for mana regeneration, enabling sustained Nova spam. This build requires careful gear optimization to maintain the 105% Faster Cast Rate breakpoint without Spirit shield.

Additional Stats & Synergies

Beyond Conviction, Infinity provides excellent stats. The 50% Chance to Cast Level 20 Chain Lightning When You Kill An Enemy adds substantial AoE clear, while 40% Chance of Crushing Blow helps mercenaries shred high-health targets. +35% Faster Run/Walk keeps mercenaries mobile, and +255-325% Enhanced Damage ensures respectable physical damage output.

Prevent Monster Heal is critical for Uber Tristram, stopping bosses from regenerating health. The 30% Better Chance of Getting Magic Items adds modest magic find value, while character-level-scaled vitality (+0.5-49.5 to Vitality) provides survivability at higher levels.

Best Bases

Mercenary Bases

Ethereal elite polearms maximize mercenary damage. Giant Thresher offers the fastest attack speed with manageable strength requirements. Thresher and Great Poleaxe provide excellent alternatives. Stygian Pike has a guaranteed 4 sockets from Larzuk's quest and lower strength requirements (66 STR), making it easier to gear mercenaries. Mancatcher has the fastest base attack speed (-20) but cannot get 4 sockets from Larzuk.

Self-Wielding Bases (Nova Sorceress)

For self-wielding, Scythe requires only 41 STR and 41 DEX, making it ideal for casters who want to minimize attribute investment. War Scythe offers slightly higher damage but requires 80 STR and 80 DEX. Ethereal bases are preferred to reduce strength requirements further, as self-wielding casters don't lose durability when casting spells.

Rune Cost & Value

Requiring two Ber runes, Infinity is among the most expensive runewords in the game. However, its impact on elemental builds cannot be overstated—it transforms mediocre clear speed into top-tier farming efficiency by enabling damage against previously immune monsters. For lightning-based builds, Infinity is not optional—it's mandatory for endgame viability.