Tanks have become especially powerful this season. The recent rune and item changes have given them an edge in durability and pushing potential within the champion pool. As such, they have left most players quite skeptical on how to take down such mighty creatures.
Nevertheless, have no fear. The following article will show you the best items and runes to use against tanks:

Items

Blade of the Ruined King

Cost: 3300 (700)
+40 Attack Damage
+25% Attack Speed
+12% Life Steal

UNIQUE Passive: Basic attacks deal 8% of the target's current Health as bonus physical damage on hit.
UNIQUE Active: Deals 100 magic damage to target champion and steals 25% of their Movement Speed for 3 seconds (90 second cooldown).

Minimum bonus physical damage dealt is 15.
Maximum bonus physical damage dealt to monsters and minions is 60.
User's Life Steal is applied to bonus physical damage dealt.

Why is it good against tanks?

• It is perfect as a first item since it gives you sustain, AS and AD at a low cost.
• Works well with stacking-items and can be used for both melee and ranged champions.
• Its passive can counter health stacking champions without the need of sacrificing AS and Crit for Lethality.

Guinsoo's Rageblade

Cost: 3100 (790)
+25 Attack Damage
+25 Ability Power
+25% Attack Speed

Passive: Basic attacks deal 15 magic damage on hit.
UNIQUE Passive - Last Whisper: Gain 15% Armor Penetration.
UNIQUE Passive - Dissolve: Gain 15% Magic Penetration.
UNIQUE Passive: Basic attacks grant +8% Attack Speed for 5 seconds (up to 6 stacks). At max stacks, gain Guinsoo's Rage.

Guinsoo's Rage: Every 3 basic attacks, trigger on hit effects twice.
While at half stacks, melee champions' next attack will fully stack Rageblade.

Why is it good against tanks?

• Rageblade is one of the most powerful power-spike items in the game. Especially for champions that have their own AS like Master Yi, Jax, etc.
• It has both Armor and Magic-pen to fight against tanks and it also boosts your on-hit damage.
• It is also a great first pick item that cleaves minions and monster camps like butter.

Mortal Reminder

Cost: 2800 (550)
+45 Attack Damage

UNIQUE Passive - Last Whisper: +25% Armor Penetration
UNIQUE Passive - Executioner: Physical damage inflicts Grievous Wounds on enemy champions for 5 seconds.

Why is it good against tanks?

• Mortal reminder is one of the best armor-piercing items that ignore 25% of the enemy’s armor and applies grievous wounds to reduce self-healing.
• It is relatively cheap and efficient for both melee and ranged champions. 
• It is mostly used as a late-game counter against armor stacking champions like Rammus and Malphite or for self-healing champions like Volibear and Swain. 

The Black Cleaver

Cost: 3000 (950)

+400 Health
+40 Attack Damage
+20% Cooldown Reduction

UNIQUE Passive: Dealing physical damage to an enemy champion Cleaves them, reducing their Armor by 4% for 6 seconds (stacks up to 6 times, up to 24%).
UNIQUE Passive - Rage: Dealing physical damage grants 20 movement speed for 2 seconds. Assists on Cleaved enemy champions or kills on any unit grant 60 movement speed for 2 seconds instead. This Movement Speed is halved for ranged champions.

Why is it good against tanks?

• Black Cleaver is mostly used for melee fighters in the top-lane like Darius and Garen that rely on MS to engage enemies.
• It is a well-balanced first pick item that gives you both offensive and defensive strength with a 20% cooldown on your abilities.
• It works well with other stacking items like Rageblade to get the 24% Armor-pen faster to combat tanks.

Liandry's Torment

Cost: 3100 (750)
+75 Ability Power
+300 Health

UNIQUE Passive - Madness: Deal 2% more damage for each second in combat with champions (10% maximum).
UNIQUE Passive - Torment: Spells burn enemies for 3 seconds, dealing bonus magic damage equal to 1.5% of their maximum Health per second. Burn damage is increased to 2.5% against movement-impaired units.

Why is it good against tanks?

• Liandry’s Torment is a popular item pick that is well known for its burns. It is like a mini ignite for all your abilities.
• It works well with AOE items and spells that utilize its passive to melt tanky champions.
• It is a great power-spike item that increases your AP and HP. This allows you to sustain damage while you dish out even more.

Morellonomicon

Cost: 3000 (550)
+70 Ability Power
+300 Health

UNIQUE Passive - Touch of Death: +15 Magic Penetration
UNIQUE Passive - Cursed Strike: Magic damage dealt to champions inflicts them with Grievous Wounds for 3 seconds.

Why is it good against tanks?

• An AP item that does grievous wounds is very rare and even more powerful. It opens up the enemy tank’s defenses so you and your team can kill him.
• Works well with Liandry’s Torment to get that bonus added effect on Grievous wounds and burns. 
• It is a great offensive and defensive item to combat tanks that use CC as they take more damage than they can dish out.

Tips: 

Items such as Duskblade of Draktharr: 

Edge of Night:

Youmuu's Ghostblade:

may have lethality but it is mostly used by assassins to combat squishy champions and therefore cannot combat tanks.

Lol Best Runes Against Tanks

Press the Attack

PASSIVE: Basic attacks against enemy champions apply stacks for 4 seconds. Attacking a new target removes all stacks from the previous target. The third stack consumes them all to deal 40 − 180 (based on level) bonus Attack damage Ability power Adaptive damage and makes them Exposed for 6 seconds, causing them to take 8% − 12% (based on level) increased damage from all subsequent sources (except from true damage).

Cut Down

PASSIVE: Deal 5% to 15% more damage to champions, based on how much more maximum health they have than you. Bonus damage scales up linearly against enemies with 10% to 100% more maximum health than you.

Conqueror

PASSIVE: Basic attacks or abilities that deal damage to an enemy champion grant 1.2 − 3.6 (based on level) bonus Attack Damage or 2 − 6 (based on level) Ability Power (Adaptive) for 2 seconds, stacking up to 5 times, for a maximum of 6 − 18 (based on level) bonus Attack Damage or 10 − 30 (based on level) Ability Power (Adaptive).
When fully stacked, 8% of your damage against champions is converted to true damage and you heal for 8% of the pre-mitigation damage dealt. The buffs refresh upon dealing damage to enemy champions with attacks or abilities.

Cheap Shot

PASSIVE: Basic attacks and damaging abilities deal 10 − 45 (based on level) bonus true damage to Slow icon slowed or Stun icon immobilized enemy champions.

Sudden Impact

PASSIVE: Going in combat by affecting an enemy champion within 3 seconds of using a dash, blink or Teleport, or exiting from Twilight Shroud old2 invisibility or Ambush 2 camouflage, grants 7 Lethality (4.36 − 7 (based on level) armor penetration) and 6 Magic Penetration for the next 5 seconds.

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