PHextech Capacitor
Jayce can swap between melee and ranged weapons using Mercury Cannon / Mercury Hammer starting from level 1. Swapping weapons also swaps all his Abilities and grants him 30 Move Speed for 0.75 seconds.
Champions
Displayed data version: 16.19.1 · Patch 26.19
Latest attempt: No changes · Sep 28, 2026, 2:55 PM JST
Sources are checked every 6 hours, or every 3 hours on Wednesdays and Thursdays (JST). Changed sources or compiler code trigger regeneration and validation before applying. Start times may be delayed.
This page uses a pinned Data Dragon snapshot. It is not a verification of every in-game interaction or hotfix.
Stats and stacks calculate the state you enter. Nine outputs that cannot be derived from the source require in-game values. Special copied or possessed recasts and transfer restrictions are outside full simulation coverage.
This catalog covers normal Summoner’s Rift. Excluded does not mean removed from the game. The classification and its source are listed below.
Content language: English

the Defender of Tomorrow
Select forms, weapons or follow-up abilities. Empowered and evolved effects also appear in the ability descriptions.
Variable valuesScaling & formulas
Jayce can swap between melee and ranged weapons using Mercury Cannon / Mercury Hammer starting from level 1. Swapping weapons also swaps all his Abilities and grants him 30 Move Speed for 0.75 seconds.
Mercury Hammer: Jayce leaps to an enemy, dealing (60 + 135% Bonus attack damage) physical damage to surrounding enemies and Slowing them by 35% for 2 seconds.
Mercury Hammer - Passive: Jayce's Hammer Attacks grant 15 Mana.
Mercury Hammer - Active: Jayce creates an electric aura dealing (140 + 100% Ability power) magic damage over 4 seconds.
Hammer Form: Jayce swings his hammer, Knocking Back his target and dealing 100% Bonus attack damage plus 8% max Health magic damage.
Mercury Hammer: Jayce transforms his weapon into the Mercury Cannon, gaining Attack Range and new Abilities. Jayce's next Attack removes 20%((Lv1–5: 20 / Lv6–10: 25 / Lv11–15: 30 / Lv16–20: 35)%) Armor and Magic Resist for 5 seconds.