Best Support Gems for Contagion
60 support gems fit Contagion in Path of Exile 2. 3 raise all of its damage or speed with a fixed multiplier; the biggest: Hourglass (×1.3, cost ×1), Deliberation (×1.2, cost ×1), Considered Casting (×1.15, cost ×1.15). 5 more only multiply one kind of damage (physical, hits, area, ailments…), and 12 only work under a condition. Patch 0.5.5, from the game files.
3 supports that multiply all of Contagion's damage
#1×1.3all damagecost ×1
#2DeliberationSupported Skills deal 20% more Damagealso: 30% more Movement Speed penalty while using Supported Skills×1.2all damagecost ×1
#3Considered CastingSupported Spell Skills have 15% less Cast SpeedSupported Spells deal 35% more Damage×1.15all damagecost ×1.15
5 supports for one kind of damage
These help only the part of Contagion's damage they name: physical, hits, area, damage over time, or an ailment it has to inflict first.
#1Concentrated AreaSupported Skills deal 30% more Area Damagealso: Supported Skills have 50% less Area of Effect×1.3area damagecost ×1
#2Swift Affliction ISupported Skills deal 30% more non-Ailment Damage over Timealso: 20% less Duration of Supported Skills and Damaging Ailments they inflict×1.3non-ailment damage over timecost ×1
#3Swift Affliction IISupported Skills deal 30% more non-Ailment Damage over Timealso: 10% less Duration of Supported Skills and Damaging Ailments they inflict×1.3non-ailment damage over timecost ×1
#4Brutality IISupported Skills deal 30% more Physical Damage×1.3physical damagecost ×1.2
#5Brutality IIISupported Skills deal 30% more Physical Damagealso: Hits with Supported Skills have 20% chance to ignore Enemy Physical Damage reduction×1.3physical damagecost ×1.2
12 supports that need a condition
#1Derangerecommended by the gameonly sometimes: Supported Skills deal 8% more non-Ailment Damage over time per 100 Intelligence×1conditionalcost ×1
#2Drain Ailmentsrecommended by the gameonly sometimes: Supported Skills Consume all Ailments of a random type on the target when inflicting damage over time Debuffs, causing the Debuff to deal 35% more damage if any Ailments were consumed×1conditionalcost ×1
#3Intense Agonyrecommended by the gameonly sometimes: Damage over time with non-Ailment Debuffs inflicted on full-life enemies by Supported Skills deal 50% more damagealso: Supported Skills have 25% less Skill Effect Duration×1conditionalcost ×1
#4Minion Pact Irecommended by the gameonly sometimes: Supported Skills remove 100% of your maximum Life from a nearby Minion on use to deal 30% more damage×1conditionalcost ×1
#5Minion Pact IIrecommended by the gameonly sometimes: Supported Skills remove 150% of your maximum Life from a nearby Minion on use to deal 35% more damage×1conditionalcost ×1
#6Profanity Irecommended by the gameonly sometimes: Supported Skills deal 30% more Chaos Damage if consuming a Corpsealso: Supported Skills consume a Corpse within 5 metres on use, if possible×1conditionalcost ×1
#7Profanity IIrecommended by the gameonly sometimes: Supported Skills deal 5% more Chaos Damage for each Corpse consumed this wayalso: Supported Skills consume up to 10 Corpses within 5 metres on use, if possible×1conditionalcost ×1
#8Rageforged Ionly sometimes: Supported Skills spend 10 Rage if possible to deal 35% more Damage×1conditionalcost ×1
#9Rageforged IIonly sometimes: Supported Skills spend 10 Rage if possible to deal 35% more Damagealso: Supported Skills have 30% chance to gain the benefits of this Support without spending additional Rage×1conditionalcost ×1
#10Swift Affliction IIIonly sometimes: Supported Skills deal 50% more non-Ailment damage over time if their duration is less than one secondalso: 30% less Duration of Supported Skills and Damaging Ailments they inflict×1conditionalcost ×1
#11Zenith IIonly sometimes: Supported Spells deal 30% more Damage while you are above 90% of your Maximum Manaalso: Supported Skills have 25% increased Mana Cost Efficiency×1conditionalcost ×1
#12Varashta's Blessingonly sometimes: Supported Skills deal 10% more Damage for each different Command Skill you have used in the last 15 seconds×1conditionalcost ×1.2
Left out, outclassed by a higher tier of the same family (one per family per skill): Brutality I (by Brutality II), Zenith I (by Zenith II).
How it is counted
Which supports fit Contagion: the game's skill types with Path of Building's rules (the full list). Multiplier = product of the support's "X% more/less Damage" and "more/less Attack, Cast or Skill Speed" lines; a line limited to one kind of damage (physical, hits, poison magnitude…) is kept to that kind. Cost = the support's cost & reservation multiplier (GrantedEffectsPerLevel.CostMultiplier).
Assumptions
- "% increased" lines, crit multipliers and utility (more projectiles, chains, area) are not multipliers here: their worth depends on your build.
- A multiplier for physical damage only helps the physical part of Contagion's damage, and so on for each kind.
- Read the "also" lines: some supports add a cooldown or a cost in Glory or Combo.