Onslaught

Onslaught is a buff that grants 20% increased attack speed, cast speed, and movement speed.^[1]

The effects of Onslaught are affected by increased Buff Effect, which can only be obtained through the use of IchimonjiIchimonji
Corsair SwordOne Handed Sword
Physical Damage: (45-58.5) to (167.4-195)
Critical Strike Chance: 5.00%
Attacks per Second: (1.86-1.94)
Weapon Range: 1.1 metresRequires Level 58, 81 Str, 117 Dex40% increased Global Accuracy Rating(80-95)% increased Physical Damage
Adds (5-10) to (13-20) Physical Damage
(20-25)% increased Attack Speed
10% increased Effect of Buffs on you
10% increased Mana Reservation Efficiency of Skills
Allies' Aura Buffs do not affect you
Your Aura Buffs do not affect alliesMaster yourself before you seek to master others.. The duration of Onslaught cannot be increased by the duration passive nodes because these only increase the duration of buffs applied by skills.

Sources

Items

Silver FlaskSilver FlaskLasts 6.00 Seconds
Consumes 40 of 60 Charges on use
OnslaughtRequires Level 27Right click to drink. Can only hold charges while in belt. Refills as you kill monsters.
Death RushDeath Rush
Amethyst RingRequires Level 30+(17-23)% to Chaos ResistanceRecover (3-5)% of Life on Kill
Gain Adrenaline for (1-3) seconds on KillTo truly appreciate life you must be there when it ends
Daresso's DefianceDaresso's Defiance
Full DragonscaleArmour: (1316-1731)
Evasion: (1044-1372)
Movement Speed: -3%Requires Level 63, 115 Str, 94 Dex(180-220)% increased Armour and Evasion
+(60-90) to maximum Life
2% of Physical Attack Damage Leeched as Life
You lose all Endurance Charges when Hit
You gain an Endurance Charge on Kill
You gain Onslaught for 5 seconds per Endurance Charge when Hit
100% increased Effect of Onslaught on you"When your back is against the wall,
And your opponent is bleeding you dry,
There is only one appropriate response:
Unbridled, overwhelming violence."
- Daresso, the Sword King
Extractor MentisExtractor Mentis
Agate AmuletRequires Level 16+(16-24) to Strength and Intelligence+(30-50) to Strength
Recover 1% of Life on Kill
5% chance to grant Onslaught to nearby Enemies on Kill
5% chance to grant Chaotic Might to nearby Enemies on Kill
10% chance to gain Onslaught for 10 seconds on Kill
10% chance to gain Chaotic Might for 10 seconds on KillWhen slaughtered flesh falls silent,
the soul may yet scream on.
Kongor's Undying RageKongor's Undying Rage
Terror MaulTwo Hand Mace
Physical Damage: (144-157) to (467-537)
Critical Strike Chance: (7.80-8.40)%
Attacks per Second: 1.15
Weapon Range: 1.3 metresRequires Level 67, 212 Str25% chance to double Stun DurationAdds (43-56) to (330-400) Physical Damage
(30-40)% increased Critical Strike Chance
+(15-20)% to all Elemental Resistances
Hits can't be Evaded
Your Critical Strikes do not deal extra Damage
You gain Onslaught for 4 seconds on Critical StrikeCommand like a king and nothing will stand in your way.
Relentless FuryRelentless Fury
Decorative AxeOne Handed Axe
Physical Damage: (48-57.6) to (91.2-108)
Critical Strike Chance: 5.00%
Attacks per Second: 1.20
Weapon Range: 1.1 metresRequires Level 29, 80 Str, 23 Dex(60-80)% increased Physical Damage
Adds (3-5) to (7-10) Physical Damage
2% of Physical Attack Damage Leeched as Life
Culling Strike
You gain Onslaught for 3 seconds on Culling Strike
100% chance to Avoid being Chilled during OnslaughtRelentless fury
Sunder my every foe
Fuel my boiling blood
RotgutRotgut
Quicksilver FlaskLasts (7.80-9.00) Seconds
Consumes 30 of 60 Charges on use
40% increased Movement SpeedRequires Level 4050% chance to gain a Flask Charge when you deal a Critical Strike
(30-50)% increased Duration
Consumes Frenzy Charges on use
Gain Onslaught for 3 seconds per Frenzy Charge consumed on useRancid, rotten, and wicked are those that dare to taste my serum.Right click to drink. Can only hold charges while in belt. Refills as you kill monsters.
Vaal CaressVaal Caress
Bronzescale GauntletsArmour: (110-148)
Evasion: (110-148)Requires Level 27, 22 Str, 22 Dex+5 to Level of Socketed Vaal Gems
-5 to Level of Socketed Non-Vaal Gems
(120-140)% increased Armour and Evasion
+(50-70) to maximum Life
+40% to Cold Resistance
You gain Onslaught for 20 seconds on using a Vaal Skill"The gems are strangely human at times.
They simply love to be held."
- Doryani, First Seer to the Queen
Mutewind PennantMutewind Pennant
Enameled BucklerChance to Block: 24%
Evasion: (559-698)
Movement Speed: -3%Requires Level 42, 103 Dex6% increased Movement Speed(80-100)% increased Evasion Rating
+(20-40)% to Cold Resistance
10% increased Area of Effect
Gain Onslaught for 4 seconds when you Warcry
25% increased Warcry Buff Effect
Warlord's CallEmbrace the snow or be buried.
Ahn's HeritageAhn's Heritage
Colossal Tower ShieldChance to Block: 29%
Armour: (783-1202)
Movement Speed: -3%Requires Level 67, 159 Str+(10-20) to maximum Life(50-100)% increased Armour
+(60-80) to maximum Life
-1 to Maximum Endurance Charges
-10% to maximum Chance to Block Attack Damage
+6% Chance to Block
+2% to all maximum Resistances while you have no Endurance Charges
You have Onslaught while at maximum Endurance Charges"It's not Karui, Azmeri or even Vaal in origin,
but one thing is certain. It is very, very old."
- Icius Perandus, Antiquities Collection, Item 46
PerseverancePerseverance
Vanguard BeltRequires Level 78+(260-320) to Armour and Evasion Rating(4-8)% increased maximum Life
+(20-40)% to Cold Resistance
1% increased Attack Damage per 200 of the lowest of Armour and Evasion Rating
Melee Hits which Stun Fortify
You have Onslaught while Fortified"Some blows must be evaded. Some blows must be endured.
The trick is to tell them apart."
- Daresso, the Sword King