Reverberation

Stats

Values as the League of Legends Wiki's item data lists them, for every mode; the data doesn't state their units.

Effects

• Reverberate (unique): After 2 seconds from the start of the combat phase in each round, gain 5 bonus health per 1% bonus attack speed.
• Resonate (unique): Basic attacks on-hit deal 10 (+ 2% of your bonus health) bonus magic damage.
• Rumble (unique): Upon immobilize or immobilize an enemy, your on-hit effects are applied to them 3 times.³

• A crowd-control tank build with Reverberation or Ethereal Weapon, Mystic Punch, Reaper's Toll, and a tank item can beat an opponent if it lands its crowd control first.⁵
• With Rammus, Mystic Punch and Reverberation can repeatedly reset Q; Essence Reaver can help sustain its mana cost.⁶
• For Briar, Mystic Punch, Ethereal Weapon, Reverberation, Double Tap, and Reaper's Toll can make Q repeatedly apply Reaper's Toll and reset itself; the number of applications is uncertain.⁷
• Briar can use Reverberation, Ethereal Weapon, and Mystic Punch to repeatedly cast Q.⁸
• For a Pantheon build centered on repeated stuns, use Reverberation, Mystic Punch, and Ethereal Weapon; Hullbreaker, Black Cleaver, Titanic Hydra, Blade of the Ruined King, and Mercurial Treads are additional options.⁹
• With red Kayn, Reverberation, Mystic Punch, and Firebrand can keep enemies airborne while stacking burn.¹⁰
• A Rammus build with Reverberation, Darksteel Talons, Shrink Engine, Mystic Punch, and Ethereal Weapon can remove Q's cooldown; Muramana, Blade of the Ruined King, and Seraph's Embrace are additional items in the build.¹¹
• A Rammus build with Protein Shake, Sword of Blossoming Dawn, Reverberation, armor and magic resistance multipliers, Dragon Heart, and attack speed limit augments can convert its bonuses into healing, shields, attack speed, and bonus health.¹²
• A full on-hit Qiyana build with Reverberation, Juiced, and full mana can make Qiyana's stuns deal heavy damage.¹³
• For Quinn, Force of Entropy, Reverberation, and Mystic Punch can let E repeatedly push enemies while they are crowd controlled.¹⁴
• With Nautilus, using W before the combo can deal more on-hit damage than using it as an auto reset, because the combo includes W's on-hit effect, his passive, and Q or R.¹⁵
• For Braum, use Darksteel Talons and Reverberation with Dashing; using W on a teammate before the buff expires can infinitely stack armor.¹⁶
• If you find Reverberation, Ethereal Weapon, or Double Tap, spend resources looking for a synergy such as Firebrand, Mystic Punch, Darksteel Talons, or Reaper's Toll; relying only on legendary items for on-hits is not very strong.¹⁷
• A Rakan on-hit build with Reverberation, Mirage Blade, and Ethereal Weapon can use Rakan's ultimate and repeated W casts on grouped champions to keep them from moving; additional on-hit effects or tank items can help the build.¹⁸

• Reverberation, Ethereal Weapon, and crowd-control tanks can proc Hullbreaker instantly and trigger Titanic Hydra multiple times.¹⁹
• Force of Entropy and Reverberation can apply many on-hit effects during crowd control.²⁰
• Reverberation can trigger Titanic Hydra's active.²¹
• On-hit effects from Reverberation can apply Firebrand stacks three times with each Q, E, or R.²²
• Reverberation and Mystic Punch can trigger Terminus on-hit, granting its penetration and armor and magic resistance.²³
• Reverberation and Moonflair Spellblade can pair with Mystic Punch on Quinn; Mirage Blade can also be used instead of Mystic Punch.²⁴
• Firebrand and Conduit can mimic the interaction between Mystic Punch and Reverberation.²⁵
• Ornn's ultimate can trigger Reverberation multiple times, applying more than three on-hit effects with one ultimate.²⁶
• Blitzcrank's Q with Reverberation, Reaper's Toll, and Ethereal Weapon can apply on-hit effects repeatedly during R.²⁷
• Reverberation, Mystic Punch, and crowd control form a favored combination.²⁸
• Reverberation, Moonflair Spellblade, Mystic Punch, and Ethereal Weapon can form a combination centered on repeated crowd control.²⁹
• Alistar can use Courage of the Colossus, Mystic Punch, and Reverberation with Protein Shake, Cloak of Starry Night or Dragon King's Crown, and Dragonheart for mana.³⁰
• Alistar can use Mystic Punch, Ethereal Weapon, Reverberation, Moonflair Spellblade, and Force of Entropy with his knock-up.³¹
• Briar, Jax, Yasuo, and Yone can be strong with Mystic Punch and Reverberation.³²
• Xerath can use Reverberation or Ethereal Weapon with Spellblade; the item also makes his plants stronger and easier to take.³³
• Reverberation, Mystic Punch, and Mirage Blade can give Blitzcrank an infinite knock-up loop without first stacking Reverberation.³⁴
• Twisted Fate's empowered auto, Vayne's W, Yunara's Q, and Ashe's Q can gain stacks from Reverberation's on-hit effects; the counter increment for abilities that require a set number of attacks is itself an on-hit effect.³⁵

• Since patch 26.9, Reverberation no longer needs to stack to apply on-hit effects when immobilizing a target.³⁶
• Since patch 26.9, Reverberation no longer needs to stack before it can trigger its on-hit effects; previously, it needed three stacks.³⁶³⁷

Earlier formats

• Reverberation was paired with Moonflair Spellblade and Blade of the Ruined King on Galio.³⁹ 8x2 duos
• Reverberation was paired with Hullbreaker on Blitzcrank.⁴⁰ 8x2 duos
• Maokai could sometimes build tanky on-hit with Titanic Hydra and Blade of the Ruined King instead of full tank, especially with Vulnerability.⁴¹ 8x2 duos
• Berserk did not count as immobilizing an enemy for Reverberation.⁴² 8x2 duos