A reference for what each unit stat in Teamfight Tactics actually means and how it scales. This focuses on combat mechanics — nothing about economy, shop odds, or level-up costs.
Health, Shield, and Mana
Health (HP)
The unit's life pool. When it reaches 0 the unit dies. Base HP is listed on the unit card; star-ups multiply it (typically ~1.8× per star). Many tank items and traits scale off max HP, which is the post-buff value.
Shield
A separate pool that absorbs damage before HP. Shields are usually temporary, apply on top of max HP, and do not interact with healing. Some shields only block a specific damage type (physical, magic, or "next N instances").
Mana
Units cast their ability once current mana reaches max mana. Mana is generated in two ways:
- On attack — a flat amount per basic attack regardless of attack speed (roughly 10 for ranged carries, 7 for casters, 5 for tanks).
- On damage taken — tanks gain ~1% of pre-mitigation damage plus ~3% of post-mitigation damage, capped at ~42.5 mana per hit.
Starting Mana
Mana the unit begins combat with. A unit with 30 starting mana and 60 max mana only needs to fill 30 mana before its first cast. Items like Blue Buff raise starting mana.
Attack speed vs. mana items: casts over a fight
Same base unit (30 starting mana, 0.75 base AS, 10 mana per attack), simulated across 30 seconds of combat with four item configurations. Two scenarios: a low-mana unit (40 max mana) and a heavy caster (120 max mana).
Low-mana unit — 40 max mana
No items (6 casts)
+ Guinsoo's Rageblade (10 casts)
+ Blue Buff (8 casts)
+ Spear of Shojin (8 casts)
Simulation assumes a 1-second mana lock after each cast, mana overflow is not carried (cast resets mana to 0), and Rageblade stacks gain +7% base AS per elapsed second (capped at 5.0 total AS).
Heavy caster — 120 max mana
No items (2 casts)
+ Guinsoo's Rageblade (3 casts)
+ Blue Buff (3 casts)
+ Spear of Shojin (3 casts)
Simulation assumes a 1-second mana lock after each cast, mana overflow is not carried (cast resets mana to 0), and Rageblade stacks gain +7% base AS per elapsed second (capped at 5.0 total AS).
- On the 40-mana unit, Rageblade runs away with it (10 casts vs. 6–8 for the mana items). The refill phase is tiny, so most of the cycle is the mana-lock floor — shortening the refill with AS hits that floor faster and starts the next lock sooner.
- On the 120-mana unit, the mana items catch up. Filling 120 mana is long enough that Blue Buff's +5/sec becomes a ~40% speedup. Rageblade only reaches 3 casts (vs. 2 base), roughly tied with Blue Buff and Shojin.
- Blue Buff vs. Shojin are almost identical on both charts. That's math: Shojin's 5 bonus mana per attack at 0.75 AS is ~3.75/sec, plus its 1/sec regen ≈ 4.75/sec — essentially Blue Buff's flat 5/sec. They diverge if the unit is faster: Shojin scales with AS, Blue Buff doesn't.
- Takeaway: low-mana casters prefer Rageblade (more attacks = more cast loops); high-mana casters benefit more from mana items, though Rageblade stays competitive thanks to the ramp. Units that need one cast to matter (burst carries, big-ult tanks) almost always prefer a mana item for the earlier first cast.
Attack Damage (AD) and Attack Speed (AS)
Attack Damage (AD)
The flat physical damage dealt by a basic attack. AD is shown as an absolute number (e.g. 70), but most items and traits grant percent AD — a multiplier on base AD. "+50% AD" on a unit with 70 base AD adds 35, for 105 total.
Attack Speed (AS)
Basic attacks per second. A value of 0.75 means one attack every 1.33 seconds. AS bonuses are multiplicative on base AS; a unit with 0.75 base AS and +40% AS attacks at 1.05/s. Attack speed is hard-capped at 5.0 in most sets.
Why AD and AS are two knobs
Attack-based damage per second is
AD × AS. Stacking one without the other has diminishing value — a carry with huge AD but no AS attacks too slowly to apply it, and vice versa. Most AD carries want both, plus crit.Ability Power (AP)
What AP is
AP is a percentage multiplier on ability effects, not a flat damage number. Every unit starts at 100 AP, which represents the base-case ability values printed in the tooltip. An item that grants "+20 AP" means your ability deals 120% of its listed values.
What AP scales
AP scales whatever the ability designer tagged as scaling: damage, shield size, healing, buff strength, duration, etc. Things that are explicitly not scaled by AP are left as fixed values in the tooltip (e.g. a pure crowd-control stun duration). A +AP item is only as useful as the AP-scaled numbers in a unit's kit.
AP vs. spell damage
Some abilities deal physical damage and can crit; others deal magic damage and scale with AP but cannot crit by default. A few abilities scale off AD — those usually say so in the tooltip and are classified as "attack"-type casts for item purposes (Jeweled Gauntlet, Infinity Edge, etc.).
Critical Strike
Crit Chance
Probability that a basic attack critically strikes. The default base is 25%. Crit chance is hard-capped at 100%, but excess chance isn't wasted — see "overflow" below.
Crit Damage Multiplier
How much a crit hits for. Base is 140% of normal damage (a +40% bonus). Items like Infinity Edge and Jeweled Gauntlet add to this multiplier.
Overflow past 100%
Any crit chance above 100% converts 1-for-1 into additional crit damage. A unit sitting at 130% crit chance with a 150% multiplier effectively crits every attack for 180% damage. This is why stacking crit chance past the cap is still valuable.
Abilities and crit
By default, magic-damage abilities cannot crit. Certain items (e.g. Jeweled Gauntlet, Infinity Edge) unlock ability crits; a unit needs both the unlock and crit chance for an ability to benefit.
Armor and Magic Resist
Armor
Reduces incoming physical damage. Damage reduction uses
armor / (100 + armor):- 0 armor → 0% reduction
- 50 armor → 33% reduction
- 100 armor → 50% reduction
- 200 armor → 67% reduction
- 400 armor → 80% reduction
Magic Resist (MR)
Identical formula to armor, but for magic damage. A unit can have very different armor and MR values — a strong tank vs. AD carries might melt to AP comps if its MR is low.
Shred and Sunder
Shred reduces MR by a percentage; Sunder reduces armor by a percentage. They're applied multiplicatively to the target's current value and cannot push it below 0 — armor/MR are floored at 0, at which point all damage is taken as if against true damage.
True Damage
Ignores armor and MR entirely. It still interacts with durability and damage amp.
Damage Amp and Durability
Damage Amp
A multiplier on damage dealt. +15% damage amp means every attack and ability deals 15% more. Multiple amp sources are usually multiplicative with each other.
Durability
A multiplier on damage taken. +20% durability means the unit takes 20% less damage. Durability is applied after armor/MR, stacks multiplicatively with those, and works against all damage types including true damage.
Order of operations
For a physical hit:
- Attacker's base damage × (1 + damage amp)
- × armor reduction (for physical) or MR reduction (for magic)
- × (1 − durability)
- − flat shield absorption, then HP
Ability Scaling
How tooltips encode scaling
An ability's tooltip lists base values per star level (1★ / 2★ / 3★). Those values are what the ability does at 100 AP with no modifiers. The in-game damage is:
tooltip_value × (AP / 100) × (1 + damage_amp) × target_resist_reduction × (1 − durability)
AP-scaled abilities
The most common case. Every damage or healing number in the tooltip is multiplied by AP/100. A Rabadon's Deathcap-style +50 AP item means ability damage is 1.5× baseline.
AD-scaled abilities
Some abilities explicitly use AD — usually marksmen or bruisers whose casts are an empowered attack. Tooltip lines like "deals 180% of Attack Damage as physical damage" scale directly with that unit's AD, not AP. These casts typically can crit.
Attack-speed-scaled abilities
A handful of kits tie their cast to attack speed — Jinx's rockets, Kalista-style passives, etc. More AS means more casts per second or stronger stacking effects. Mana-per-attack units also cast more frequently with more AS, so attack speed functionally scales their ability DPS.
Max-HP-scaled abilities
Tank abilities often scale off the caster's max HP (shields, self-heals, thorns-style damage). HP items then double as ability power for those units.
Percent-max-HP damage
Some abilities deal a fixed percentage of the target's max HP — it's the answer to stacking pure tank stats. That damage still goes through armor/MR and durability, so it isn't true damage unless the tooltip says so.
Range
How range works
Measured in hexes. Range 1 is melee (adjacent hex), range 4 hits from four hexes away. Range determines attack distance and, for most abilities, casting distance. Certain items (Rapid Firecannon, et al.) grant flat range bonuses.
Quick reference
| Stat | Scales | Counter |
|---|---|---|
| AD | Basic attacks, AD-scaled abilities | Armor |
| AP | AP-scaled abilities | Magic Resist |
| Attack Speed | Attack DPS, mana-per-attack | Durability, HP |
| Crit Chance | Attack damage (and ability with unlock) | Durability |
| Armor | Physical damage reduction | Sunder, true damage |
| Magic Resist | Magic damage reduction | Shred, true damage |
| Durability | All damage reduction | Percent-max-HP damage |
| Max HP | Effective HP, tank ability scaling | Percent-max-HP damage |