AP Jayce Build

General

1. You are not really AP champion, but you can make it work with two specific items!
2. You rush Hextech Rocketbelt #1, Liandry's Torment #2.
• If you are against many HP stacking champions, you can rush Liandry's Torment first.
3. You get Cosmic Insight rune to use Hextech Rocketbelt more often.
4. You poke with Hextech Rocketbelt and First Strike to earn gold and burn enemies.
5. After core items, you adapt. You can play as a tank or as a damage dealer.

General

1. Use Hextech Rocketbelt active to poke your enemies all the time, earning gold with First Strike.
2. Adapt to the enemy team. Build tanky or more damage. You can play as a utility tank, poke, or even you can go some AD items to still have plenty of damage. Depends on the team and how you want to play.
3. For utility tank, remember that Liandry's Torment works good with Serpent's Fang (to counter shields) and Oblivion Orb (to counter healing).

Items

1. If you are doing really well and want to have even more AP dmg, you can go Lich Bane, Cosmic Drive and The Collector (it procs and works nicely with DoTs).
2. If your team needs strong Physical damage, you can just go AD items.
3. Cosmic Insight reduces the cooldown of all active items, so Zhonya's Hourglass really works well with this build.

Runes

1. Wait for the First Strike and proc it with your combo, to deal damage and earn gold.
2. Be careful to not get poked, because you waste First Strike procs.

Champion

1. Your usual combo is To the Skies! / Shock Blast (Q), then Thundering Blow / Acceleration Gate (E) (not E then Q!). You first use Q, people do not expect that it will go further, and then you enhance it mid-flight with your E.
2. As Jayce, you have your 'Ultimate' Mercury Cannon / Mercury Hammer (R) since lvl 1. You can lose track of enemy levels and get surprised by their level 6 spike and their ulti. Watch out!

Cannon and Hammer Form interactions

1. Jayce is treated as melee in Hammer Form and as ranged in Cannon Form. That means there are interactions with certain runes and items. Examples below.
2. Grasp of the Undying - If you want to deal more damage, get more Health and heal for more with Grasp of the Undying - when auto from ranged, switch to melee (when animation is mid-flight)!
3. First Strike - If you play Jayce with First Strike rune, if you fire Cannon To the Skies! / Shock Blast (Q) and change to Hammer Form, you actually get the melee gold. This way you can farm and earn additional gold (up to 100-150g per minute) by coordinating E + Q with First Strike.
• Credit: Nxal
4. Hubris - if you score a takedown when in Hammer Form, you get more Attack Damage (melee effect), than you would get in Cannon Form.

Riot

1. Be sure to switch stances often. It will enhance your attacks and grant you quick bursts of speed.
2. If you find yourself taking lots of damage, try using Jayce's Hammer Stance, as it grants you additional defenses.
3. For increased range and damage, try casting Shock Blast through the Acceleration Gate.