Mobafire League of Legends Build Guides Mobafire League of Legends Build Guides

Jayce Build Guide by IonDragonX

Not Updated For Current Season

This guide has not yet been updated for the current season. Please keep this in mind while reading. You can see the most recently updated guides on the browse guides page.

Rating Pending
Like Build on Facebook Tweet This Build Share This Build on Reddit
League of Legends Build Guide Author IonDragonX

Captain Jayce, the Space Marine -WIP-

IonDragonX Last updated on August 29, 2012
Did this guide help you? If so please give them a vote or leave a comment. You can even win prizes by doing so!

You must be logged in to comment. Please login or register.

I liked this Guide
I didn't like this Guide
Commenting is required to vote!

Thank You!

Your votes and comments encourage our guide authors to continue
creating helpful guides for the League of Legends community.

Cannon / Burst / Support/ Spam


Solo / Jungle / Magic / Trollz

Ability Sequence

Ability Key Q
Ability Key W
Ability Key E
Ability Key R

Not Updated For Current Season

The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.



Offense: 15

Honor Guard

Defense: 15

Strength of Spirit

Utility: 0

Guide Top

Notice of Full Disclosure

To use this "Captain Jayce, the Space Marine" build, you must own and use the Full Metal Jayce skin.
This build might not work if you don't. :wink,wink: :nudge,nudge:

Actually Important Note:
  • The cheat sheet (the stats at the top) always leaves out stacks and buffs. It is important for you to remember that The Bloodthirster, the Maw of Malmortius and the Manamune's overall effects are "invisible" to the stats at the top. See the Items section for more explanation.
  • More importantly, the cheat sheet also leaves out Masteries. You can see that for yourself using the tooltip. This leaves an incomplete picture of this build. See the Masteries section, please.
  • The cheat sheet incorrectly adds attack speed modifiers instead of multiplying them. It is impossible for any build to have more than 2.5 attacks per second.
  • The cooldown runes that I use will actually total 10% at level 18. Mobafire doesn't have the fractions properly included because the LoL client doesn't consistently display them. I have done my due diligence and can say, for certain, that you get maximum cdr with this build.
  • In the case you are immune to humor: the "Notice of Full Disclosure" at the top of this section is a joke. You may now proceed to laugh.

Guide Top


space"Captain Jayce, the Space Marine" This title says it all, doesn't it? The purpose of this guide is to show you how to play Jayce as a Space Marine. Jayce has abilities that I feel are dismissed as novelty. They are not! They are exploits! There is a synergy to be found between his AD ratio, his cooldowns, his toughness and his flexability.

spacePlease note that all of the builds in this guide use the same runes and masteries. The differences are in the summoner skills, skill progression and item purchases. This allows your Marine to adjust to team needs on the fly. If you pick Jayce in draft and there is a hole in your team composition then you can fill that need without switching runes and masteries. (except AP carry)

Space Marine Qualities
  • Deadly.
  • Uses energy weapons.
  • Wears armor.
  • Possibly uses a force field.

How to Proceed
  • Build lots of AD!
  • Maximize cooldown reduction.
  • Increase armor and magic resistance.
  • Possibly build Banshee's Veil or Maw of Malmortius.

Credits to jhoijhoi for the template, which you can find here.

Guide Top

Pros / Cons


+ Can switch between melee or ranged
+ Damage ratios are high
+ Highest armor available while in Hammer mode (111)
+ Has a slow and a knockback/stun
+ Has a gap closer
+ Has a speed buff that can affect all of your teammates


- Dependent on items for health
- Mana problems if skills are overused
- High learning curve
- Lacks range while in cannon mode
- Lacks movement speed

Guide Top

Unique Skills

spaceTake a good look at the banner above. There are ten icons there, right? That's pretty unique for a champion to have ten skills but Jayce really doesn't. He only has seven.
spaceThe two to the far left can be thrown out. They are really the same passive in either form, giving a +40 move speed bonus for 1.25s after a transformation. Because it is dependent on the use of his R, it isn't a passive. It is an additional active on his R. Riot probably put it here to keep the R from being too cluttered. That said, this is such a small bonus that its only benefits you in combination with Acceleration Gate and spamming R to move long distances.
spaceThe two to the far right are functionally the same skill, Jayce's transformation. Obviously, this switches your attack range and skills. Not so obvious is, while in hammer mode, Jayce actually has the highest armor (111) and third highest MR (65) of any champion.
spaceThe cannon's proc on your first auto-attack will debuff the opponent. His armor and MR will be shredded by up to -25% for 5 seconds. This is plenty of time to fire all three shots from Hyper Charge by the way. If you are ganking or focus firing in a teamfight, make sure to use this debuff so your teammates deal extra damage.
spaceThe hammer's proc is also on your first auto-attack, dealing up to an additional 140 magic damage. Everyone can see this because of the bolt from the blue. Yes, this will actually work on turrets but, as always, buildings are resistant to magic damage. Think of it like a mini Sheen.

spaceJayce's ultimate is not his ultimate. My definition of an "ultimate" is a skill that swings the game into the player's favor. Some champions have that on a skill that is not their R. Jayce is one such champ. I consider Jayce's transformation to be a complicated passive.
spaceThis is used as Jayce's ultimate by the majority of the guides you will see. I can agree with that because damage that scales with your opponent's stats is literally an infinite number. But that isn't all that Jayce has.
spaceAn argument could be made that these skills combine into his ultimate because of its long range, good area of effect and high damage potential. It even has high mana cost and cooldown to boot. I can't quite agree because it is a skill shot, it is item dependent to deal high damage and it can be creep blocked.

spaceWhat would I define as his other, hidden ultimate?
Hyper Charge
spaceThis skill is what inspired me to write the Space Marine guide. So many other guides tell you to level this last because, I presume, they haven't read it properly. Let's take a look at the details. (from the wiki)

(Active): Hyper Charge
spaceA self-target ability that grants Jayce 300% bonus attack speed for his next 3 autoattacks within 4 seconds. These 3 attacks deal a percentage of his regular damage depending on its rank.
spaceCost: 40 mana
spaceCooldown: 14 / 12 / 10 / 8 / 6 seconds
spaceDamage: 70 / 85 / 100 / 115 / 130 %
  • This will grant Jayce maximum attack speed (2.5) by itself. Combined with attack speed reductions such as Nasus's Wither, he may not achieve maximum attack speed.
  • The enhanced attacks will deal the same amount as a regular autoattack only at rank 3. At ranks 4 and 5, they will deal increased damage, while at ranks 1 and 2 they deal reduced damage.
  • Activating Hyper Charge will reset Jayce's attack timer.
  • The enhanced attacks can critically strike and will stack with critical strike damage multiplicatively (i.e. at rank 5 a critical strike with no modifiers and Hyper Charge active will deal 130% * 2 = 260% damage).
  • The enhanced attacks will not pop spell shield.
  • The buff lasts for 4 seconds, total, regardless of how many attacks were used.
  • The buff will persist even if Jayce switches into Hammer Stance.
spaceGot it... memorized? Good. Here's what other people overlook:
  • This will reset the attack timer. This means you get 4 hits within 2 seconds, not 3.
  • The damage amplification is applied to all of the damage the autoattack deals. Sheen/Trinity proc? Amplified. Mercury Hammer bonus? Amplified. Madred's Bloodrazor? Amplified. Wit's End? Amplified.
  • The flip side, Lightning Field, is fantastic for farming and repelling melee champions.
  • The best for last, read the section below.

spaceI'm sorry I have to do this but I am going to resort to math. The base cooldown for rank 5 is reduced to less than half the rank 1. The final 6 second cooldown becomes very spammable when you use CDR. This build reduces it to 3.6 seconds. Because it takes at best 1.2 seconds to get the charged shots off, you could claim this buff is usable at least 33% of the time. You might try adding 33% max attack speed with 66% of .99? (Jayce at level 18) You would calculate 1.49 attacks per second, 60% of which have a +30% damage bonus. Look at that closely, now. That looks good, but its not the whole story. Activating the skill resets the timer, remember? Lets approximate the +30% damage as 1.3 auto-attacks, ok?

Hyper Charge [5] x 1.2 seconds = 3.9 Hits
Jayce (.993 AS) x 2.4 seconds = 2 hits
5.9 hits / 3.6 seconds = 1.639 hits per second
1.639 hits per second - Jayce (.993 AS) = .648 additional attack speed
.648 / base .658 = 198% attack speed

spaceTHAT does break the rules. Other than a CDR source, that equation is without any equipment. Perhaps you could think of this skill as: (Passive) Jayce gains +98% Attack Speed at a cost of 8 mana per auto-attack. Can be toggled off. O.O I like that!
spaceIf you get your attack speed over 1.25 with, oh say, a Wit's End (+40%), that will get you a third normal auto before the cooldown cycles again. With that factored in, we would be adjusting this "passive" to +140% attack speed and 7 mana per shot. That said, if you build even more attack speed, there are diminishing returns. You can't get in a 4th hit in 2.4 seconds until you have +105% AS, a 5th requires +170% and a 6th requires +230%. That is a LOT of money thrown into a redundant stat.

Guide Top

Runes, Masteries and Summoner Spells


Greater Mark of Scaling Attack Damage

Greater Seal of Scaling Magic Resist

Greater Glyph of Scaling Cooldown Reduction

Greater Glyph of Scaling Magic Resist

Greater Quintessence of Scaling Cooldown Reduction

Greater Quintessence of Movement Speed
spaceNot much to see here. Combined with Brute Force and Deadliness , these give your Space Marine a total of only 55 AD at the start of the game. Not a big start like a ranged carry but you must remember that you are an AD caster, not a carry.
spaceThese per level runes break even with the flats at level 7, so levels 1 thru 3 will seem weak but levels 4 thru 6 will only seem mildly weaker. If you are not as confident in your early game abilities, Greater Mark of Attack Damage would start you with 7 more but end 13 less at max level.
spaceMagic damage is typically what will burst you down during the late game and Jayce's MR only grows in hammer mode. I find that these seals are always good. Don't bother with Greater Seal of Magic Resist, they are obsolete at level 7. If magic damage actually is a problem really early, buy a Null-Magic Mantle asap.
spaceCombined with Sorcery (2) and Enlightenment (3), this combo gives 20% CDR at level 18. With Frozen Heart or at least a Glacial Shroud, your skills are almost constantly available.
spaceYes, Jayce is slow. Because I delay building a Zeal, Jayce needs the extra Move Speed to prevent being camped and ganked too easily. Never forget that your position is a matter of life and death. You do NOT want to be the slowest champion in the Rift. If you are really confident in your survival skills and map awareness, you could use Greater Quintessence of Attack Damage or Greater Quintessence of Scaling Attack Damage here for extra AD.


Summoner's Wrath - Always take Wrath unless you never plan on taking Exhaust nor Ignite. I like Ignite for the +5 free AD. Don't be afraid use it early at level 1.

Brute Force - +3 AD. Still have to have it to get up the Offense Tree.

Alacrity - Negligible Attack Speed. Only necessary to get Weapon Expertise.

Weapon Expertise - An absolute MUST. Not negotiable with this build! There is no flat armor penetration to be found in this build because it utilizes % penetration by design.

Deadliness - +9 AD at level 18. Not much to see here. If you wanted to move any mastery points around at all, say for Arcane Knowledge , these would be the ones.

Sorcery - 2% CDR. Finishes this build with maximum cooldown reduction. Hitting this limit is all part of the plan, so don't remove these.


Resistance +6 MR. Magic damage is a threat the longer the game is played. Rabadon's Deathcap is popular for a reason!

Hardiness +6 Armor. Jayce needs tankyness because his hammer will put him in melee and his cannon range is short compared to other ranged characters. He has to resist the harass.

Durability +108 Health at level 18. This is one of the only sources of health in this build. Its not good to depend on Armor and MR to last in team fights but Jayce isn't supposed to be a full tank either.

Veteran's Scars +30 Health. Most valuable for levels 1 thru 3. Gotta have it because I don't use Doran's items much with Jayce.

Indomitable Ignore 1 damage each time you take damage. Partially useful. This is really a place holder to get Enlightenment, so you could move this to Summoner's Resolve or Vigor if you chose.

Enlightenment +8.1 CDR at level 18. You MUST have this. Not negotiable. This is a key component to reaching 40% CDR.

Summoner Spells

Flash: The ubiquitous summoner spell. You still have to have it to escape and secure kills.

Ignite: This is a great spell to secure a kill. While you are level 1, you should consider using it immediately, and I do mean immediately, to gain the 5 AD and 5 AP for the next 3 minutes. At level 1 with this build you have 55 AD, which is low. Bringing it to 60 helps your last hitting and eases the transition to level 4. It also really annoys your opponent to take 70 true damage right away.

Guide Top


spaceI love this overlooked combination. At worst, it is worth 115 AD but only if you don't kill anything nor take any damage. Are you playing League of Legends? Then the worst case won't happen, ya?
spaceWhat I like about this combo is, the more hurt that you are, the more damage that you do and the more life that you steal. (as well as killing the enemy) Did you know that, at half health, the Maw is actually a 75 AD item? In combat and with a decent number of stacks, this combo is likely to be in the range of 150 - 160 AD. The maximum possible is 194 but you would need to be a sneeze away from death. Realistically, you'll be doing well to get 175 at full stacks and half health. That is 60 more AD than the cheat sheet has listed. Talk about hidden bonuses!
spaceDon't forget that this combo also gives MR, which makes your health more effective and, therefore, the life steal is more effective. Also, Hyper Charge counts as auto-attacking, so you get to life steal off of that +30% damage. space"Why is a Last Whisper so important on Jayce?"
space"Well, I'm glad you asked, Timmy!" Look out, math up ahead.
spacePercent based Armor Pen is a design point to this build but they don't stack additively. W.Expertise and L.Whisper combined give 46%. How much does that do? The worst case scenario is Heimerdinger with an armor of 61. Against him, you would be ignoring 28 armor. 28 Armor Pen isn't bad, right? Now look at a proper tank with, say, 300 armor. This combo would be worth 138! That makes the 20 Armor Pen Ghostblade look kinda flimsy. Now look at the M.Cannon proc: -25% armor debuff for 5 seconds. Is this becoming clear to you? W.Expertise, L.Whisper and the M.Cannon combine to ignore 60% of the targets armor for 5 seconds. That's at least 36 Armor Pen against Heimy scaling up to 179 against the aforementioned tank!
spaceThe L.Whisper's 40 AD is often overlooked. Its not a small amount and Jayce's AD ratios will take it like any other weapon. I should also mention that Jayce's high base damage on his Shock Blast needs the Armor Pen more than it needs extra AD. At rank 5, S.Blast does 280. An I.Edge will add 92 and a L.Whisper will add 48. Which will reduce the enemy's health more? L.Whisper. Dealing 372 to 90 armor (100 -10%) would result in 195 actual damage. Dealing 328 to 54 armor (100 -46%) would deal 212! (and for less gold) The way that scaling works, armor pen is too good to be ignored.
spaceObviously, when you purchase the L.Whisper is a matter of timing. Personally, I buy it early so I can focus on other goals. I think it is THAT important! I don't want to mess up my build by constantly delaying it.

Guide Top

Best Builds : Cannon, Skill Spammer, Solo Lane and Jungle

Cannon Build

My main build. As close to a Space Marine that you can get.

Skill Spam Build

The most fun that you can have with low cooldowns. A constant stream of transformations and skill-shots coming your way!

Solo Lane Build

Sustain can be bought.

Jungle Build

Jungling and roaming systems.

Ability Explanation


  • PASSIVE PASSIVE: // explanation of ability here
  • ABILITY ONE ABILITY ONE (Q): // explanation of ability here
  • ABILITY TWO ABILITY TWO (W): // explanation of ability here
  • ABILITY THREE ABILITY THREE (E): // explanation of ability here
  • ABILITY FOUR ABILITY FOUR (R): // explanation of ability here

Ability Sequence Order

Ability Sequence
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18


// explain your ability sequence here


  • ITEM: // explain your choice here
  • ITEM: // explain your choice here
  • ITEM: // explain your choice here
  • ITEM: // explain your choice here
  • ITEM: // explain your choice here
  • ITEM: // explain your choice here

Guide Top

Niche Builds : Burst Damage, Tanky Support and Magic Damage

The glass cannon build.

Similar skills as Alistair but without the heal.

Your team nominated you to deal magic damage because they had only physical damage picks? It may feel like a desperate reaction but you can pull off dealing magic damage!

Guide Top

Troll - lo - lolz

Two troll builds. I wish these builds weren't as effective as they actually are.

Jayce fits Tiamat so well, it is almost a legitimate build and, therefore, not entirely troll.

Electric Fields have their uses.

Guide Top



Work in progress.

// summary here

// byline

// additional credits/shout-outs

Credits to jhoijhoi for the template, which you can find here.

v0.4 improved rune descriptions, added summoner spell descriptions, started mastery description. Improved formatting.

v0.35 added some text to the rune descriptions

v0.3 added a ninth build (troll 2), rewrote the magic build. filled in some paragraphs of information. Added jhoijhoi's template.

added another build, rewrote the item purchases and tweaked the mastery page.

Got in the items, runes, skills and masteries. Created the first sections. Added a picture of Full Metal Jayce.