How the Build Lab works

The Combat Power shown above the stats panel is a reference score computed from the selected champion + build + level. Aggregating stats into a single 5-digit number lets you compare the overall scale of a build at a glance.

This is not a verdict or recommendation — it just surfaces a number. How to interpret it and how to play is up to you.

Three-axis breakdown

Combat Power decomposes into three axes: Attack, Defense, and Mobility. The contributing stats and their weights:

Attack

attackDamage × 20.0
abilityPower × 12.0
attackSpeed (合算) × 400
criticalRate × (75 + criticalDamage) × 0.4
onHitMagicDamage × attackSpeed × 5.5
onHitPhysicalDamage × attackSpeed × 7.0
onHitTrueDamage × attackSpeed × 8.0
armorPenPercent × 3.0
armorPen × 3.0
magicPen × 3.0
abilityHaste × 1.2

The three on-hit terms capture per-AA bonus damage that triggers on every basic attack (e.g. Terminus' Shadow +35 magic, Kraken Slayer's true damage). Per-hit value × attack speed = DPS contribution. When Guinsoo's Rageblade is equipped, basic attacks lose their crit roll — the crit term zeroes out and the lost weight is re-allocated into the Wrath bonus (30 + crit% × 1.5, ×7/6 from Seething Strike) added onto the magic on-hit total. Exception: Caitlyn (Headshot 100% AD + 125% CRT) and Ashe (Frost Shot 10 + 100% CRT) carry passives whose damage scales with crit chance as a multiplier (not a roll), so the crit term stays intact for them even with Guinsoo.

Defense

health × 0.5
armor × 18
magicResist × 18
healShieldPower × 60.0
physicalVamp × 4.0

Mobility

moveSpeed (% 合算) × 6

Total Combat Power

combat power = (attack + defense + mobility) × build factor
build factor = 1 + (slots × 0.7)

Slots = up to 6 core items (boots included) + 1 enchant (max 7). The build editor has 12 slots, but only "core" items (upgraded + support starters, with basic/intermediate promoted to fill any gaps) score combat power. The rest sit as a visible stockpile and don't count.

What is modelled

Base stats

Champion base stats at the selected level (Lv 1–15) — health, AD, AP, armor, MR, AS, MS, etc.

Items

• Always-on stats (firm values): AD / AP / health / armor / MR / attack speed / armor pen / magic pen / regen / crit / ability haste, etc.
• Unique passives (64 items as estimates): Bloodthirster, Trinity Force, Lich Bane, Liandry's, Rabadon's, Sterak's, Black Cleaver, Death's Dance, Riftmaker, Crown of the Shattered Queen, Spear of Shojin, Edge of Night, Maw, Kaenic Rookern, Wit's End, Infinity Edge, Mortal Reminder, BORK, Nashor's Tooth, Guinsoo's, Phantom Dancer, Youmuu's, Duskblade, Guardian Angel, Manamune, Essence Reaver, Serylda's, Navori, Divine Sunderer, Eclipse, Kraken Slayer, Titanic Hydra, The Collector, Terminus, Dominik's, Iceborn Gauntlet, Sunfire Aegis, Hollow Radiance, Warmog's, Thornmail, Frozen Heart, Force of Nature, Dead Man's Plate, Heartsteel, Mantle of the Twelfth Hour, Imperial Mandate, Ardent Censer, etc. — 64 items total.
• Sample estimates: Mortal Reminder ≈ +30% armor pen / Nashor's Tooth ≈ +25 AD or +50 AP adaptive / Mejai's ≈ +50 AP (10-stack baseline).
• On-hit bonus damage (6 items): Terminus Shadow ≈ +35 magic on-hit / Wit's End ≈ +45 magic on-hit (Lv15 mid-value) / Nashor's Tooth Gnaw ≈ +25 magic on-hit (15 base + AP scaling) / Blade of the Ruined King ≈ +14 physical on-hit (Mist's Edge 12 + 1.2% current HP) / Kraken Slayer ≈ +47 true on-hit (140 mid / 3-AA equivalent) / Guinsoo's Rageblade Wrath ≈ +30 magic on-hit base (scales with crit chance up to +75, ×7/6 from Seething Strike). These feed the three on-hit terms on the attack axis as DPS contributions.
• Rabadon's Deathcap is the one multiplicative item — its 30% AP scaling applies on top of all other AP after the flat sum.
• The ★ marker on item picker cards and the combat-power panel flags items whose passive contributes via estimate.

Runes

• Always-on (8 firm values): Eyeball Collection, Zombie Ward, Legend: Alacrity, Legend: Bloodline, Overgrowth, Celerity, Absolute Focus, Gathering Storm.
• Adaptive (4 of those 8): route to AD or AP based on the build's own AP/AD balance (Mage role used as fallback when no items are picked yet).
• Proc-style (45 estimates): Electrocute, Dark Harvest, Triumph, Conqueror, Grasp of Undying, etc. Each carries an editorial flat-stat estimate. Example: Electrocute ≈ +10 AD or +20 AP equivalent.
• ★ in the rune picker and combat-power panel signals "estimate included".

Champions with editorial estimates (14)

• Champions: Senna, Smolder, Veigar, Nasus, Sion, Aurelion Sol, Bard, Kindred, Thresh, Swain, Rengar, Syndra, Jhin, Jinx.
• The first 12 stack stats permanently in-match (kills / Q hits / soul collection). Jhin (4th-bullet missing-HP bonus) and Jinx (Get Excited! takedown buff) carry conceptually different mechanics but the same editorial-estimate treatment so the combat power reflects their actual strength rather than bare-state numbers.
• Sample estimates: Senna ≈ +60 AD + 15% crit / Nasus ≈ +50 AD / Sion ≈ +150 HP / Thresh ≈ +35 armor + 35 AP / Swain ≈ +250 HP / Rengar ≈ +18 AD / Syndra ≈ +18 AP / Jhin ≈ +18 AD / Jinx ≈ +45 MS + 25% AS.
• ★ in the Scouter and ranking pages flags the estimate is applied.

Special scaling (3 champions)

• Jhin (Whisper): attack speed is fixed by passive, so item AS bonuses are dropped from the attack axis. The 4th-bullet missing-HP bonus is reflected via the +18 AD editorial estimate above (crit-triggered MS isn't modelled yet).
• Yasuo (浪人道) / Yone (狩鬼道): item and rune crit chance is multiplied ×2 and crit damage is multiplied ×0.9, modelling WR's "more crits but each hits less hard" passive trade-off.
• Critical damage: starts from WR's 175% base crit damage (+75% bonus over base). Infinity Edge adds +30% via passive — the only item currently exposing crit damage. Future crit-damage items plug into the same accumulator.
• With Guinsoo's Rageblade equipped: basic attacks lose crit roll, so the attack-axis crit term is zeroed out. The lost weight is re-allocated into the Wrath bonus (30 + crit% × 1.5, ×7/6 from Seething Strike) added onto magic on-hit. Exception: Caitlyn / Ashe have passives whose bonus damage uses crit chance as a scaling multiplier (Headshot / Frost Shot formulas), so the crit term is kept intact for them under Guinsoo.

Mobility axis dash / blink count

• Mobility axis adds per-champion dash / blink / leap count (×75 each) on top of the move-speed term, so champions like Akali / Camille / Lee Sin / K'Sante climb the axis past pure-MS leaders that don't have on-demand mobility.
• Counting rule: each player-triggered short-range movement skill (Q dash / E blink / R leap) counts once. Skills with charges (Ahri R 3-cast, Kassadin R 3-blink) count each charge. Pure MS-buff ults (Master Yi R, Dr Mundo R) don't count.
• Per-champion dash counts live in data/manual/champion_mobility.json with notes on edge cases.

What's NOT in the score

• Champion passives / active skills (general; the 14 editorial-estimate champions, 3 special-scaling champions, and dash-count axis are exceptions)
• Power-spike timing (anything time-series)
• Matchup interactions, team composition, pick / ban order
• Conditional MS buffs other than Jinx's (Sivir R / Nidalee passive / Rengar post-spell MS, etc. — uptime is too hard to estimate fairly)

Role-based Templates

After picking a champion, a "Sample" chip appears next to the My-build clear button (or next to the Self / Opponent clear in matchup mode). One tap drops a generic loadout matched to one of the official six role classifications (Tank / Fighter / Mage / Marksman / Assassin / Support) into the equipment, runes, and spells slots. Use the Comparison-build "Swap" action to hand it across for what-if iteration.

Templates are starting skeletons, not per-champion optimizations. For champion-specific best builds and matchup tuning, head to specialist sites like WildRiftFire or WR-Meta.

Matchup mode

Toggling the matchup switch on the header opens a side-by-side Self / Opponent pane for build comparison. Two design rules:

• The same champion can't be picked on both sides. The opponent picker hides whoever you've picked on the self side (and the self picker hides the opponent while matchup is on). This scopes matchup mode to different-champion comparisons and avoids the ambiguity of "viewing my own build through an opponent's lens".
• For same-champion build comparisons, turn matchup off and use solo mode's Slot 1 / 2 / 3 strip. Solo mode is the side designed to hold three parallel builds for one champion.

Caveats

Combat Power is a numeric reference, nothing more. Real match outcomes hinge on player skill, positioning, pick / ban decisions, teamwork, mental state, network conditions — none of which are modelled here. Don't trust the number too much; read it as a relative-tendency hint about your own build.

Related

• Combat Power Ranking (Lv 15, no items) →
• Release Notes →