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Stop treating Acceleration Gate like a reflex Q-E button: use it as a speed strip you can hover in and out of while you chip with autos and plain Q, then swap to hammer only after the opponent has already spent the spell that lets them stick to you
Jayce’s early lane pressure is borrowed until you cash it into a reset, and recent data fits that feel exactly: among similar top-lane poke/bully picks, he loses the most when his first component is delayed, so the point of winning walk-ups is coming back to lane with touches that now actually stick
Ahead Jayce should press the game before fights become planted-feet 30+ minute peel battles, because his leads decay harder than comparable tops there; once that slower fight shape arrives, cannon form should do most of the starting and hammer form is better used to finish or knock a diver off than to open on its own
Use hammer form once cannon form has already forced the lane or fight into a shape you like. In lane, that usually means they have spent the gap closer or commit tool that lets them stay on you, so the swap becomes a collect-or-reset button instead of a gamble. If you jump in before that, you often turn your own range advantage off and give them the long trade they wanted. In later fights, hammer is usually for finishing a chunked target, peeling a diver off your team, or knocking a fight back apart after cannon poke did the first part. If you are unsure, stay ranged one beat longer.
When Jayce swaps weapons he gains Move Speed for a short duration.
Hammer Stance: Leaps to an enemy dealing physical damage and slowing enemies.Cannon Stance: Fires an orb of electricity that detonates upon hitting an enemy (or reaching the end of its path) dealing physical damage to all enemies hit.
Hammer Stance: Passive: Restores Mana per strike. Active: Creates a field of lightning damaging nearby enemies for several seconds.Cannon Stance: Gains a burst of energy, increasing Attack Speed to maximum for several attacks.
Hammer Stance: Deals magic damage to an enemy and knocks them back a short distance.Cannon Stance: Deploys an Acceleration Gate increasing the Move Speed of all allied champions who pass through it. If Shock Blast is fired through the gate the missile speed, range, and damage will increase.
Hammer Stance: Transforms the Mercury Hammer into the Mercury Cannon gaining new abilities and increased range. The first attack in this form reduces the target's Armor and Magic Resist.Cannon Stance: Transforms the Mercury Cannon into the Mercury Hammer gaining new abilities and increasing Armor and Magic Resist. The first attack in this form deals additional magic damage.
