Last week in the LCK, DWG KIA faced off against Hanwha Life Esports, who is led by star AD carry Kim “Deft” Hyuk-kyu in the bot lane.

In game one, DK first picked Kai’Sa on blue side. In response, HLE locked in Senna. In this series, Deft debuted her brand new item build, which was also used by G2 Esports’ Martin “Rekkles” Larsson later that night in the LEC which contains three core items: Kraken Slayer, Guinsoo’s Rageblade, and Rapid Firecannon.

Guinsoo’s Rageblade, a core item of attack speed champions like Kayle and Vayne, is now bought on a champion that does not rely on attack speed — but why?

Screenshot by Amanda Tan/ONE Esports

To understand the reason pros started to play “Guinsoo Senna” in the LCK, LPL, LEC, and LCS, you first need to understand every part of this equation.

Guinsoo’s Rageblade grants 40% attack speed and 20% critical strike chance. It also converts every 1% critical strike chance into two bonus physical damage on-hit.

It’s unique passive involves stacking basic attacks. Every third attack consumes all stacks on-attack to trigger a Phantom Hit that applies on-hit effects to the target at 100% effectiveness.

As such, Guinsoo’s Rageblade and Kraken Slayer synergizes perfectly. Aside from Kraken’s 65 attack damage, 25% attack speed, and 20% critical strike chance, it shares the same stacking mechanism where every third basic attack deals additional bonus true damage on-hit.

Since it is a Mythic item, it also empowers all other Legendary items with 10% bonus attack speed, boosting Guinsoo’s power. For these reasons, Vayne, who does true damage with Silver Bolts every third attack, was the champion of this build.

Senna on the other hand, utilizes the other aspect of their combo. She’s unique because her basic attacks and Piercing Darkness (Q) apply on-hit effects, with basic attacking dealing 20% AD bonus physical damage.

You should also note that Piercing Darkness on enemy champions adds a stack on Kraken Slayer (max one stack) since patch 11.2. In this recent patch, her attack speed ratio was also buffed from 0.2 to 0.3.

Screenshot by: Kristine Tuting/ONE Esports

Absolution, Senna’s passive, makes her more powerful as the game goes on. Each Mist she collects grants her additional bonus attack, and every 20 grants her additional attack range and critical strike chance. Upon exceeding 100% critical strike chance, Senna converts 35% of the excess into life steal.

Putting everything together, Senna gets 85% with her three core items. By continually collecting wraiths, her crit stike will easily exceed 100%. Thanks to Guinsoo’s passive, her total crit strike converts to bonus physical on-hit damage — infinitely.

Since Piercing Darkness gives one stack of Kraken, Senna stacks it very quickly. As her basic attack and Piercing Darkness (Q) ability both apply on hit damage, her combo of basic attacks and Piercing Darkness (auto attack, Q, auto attack) could potentially deal over 200 on-hit damage in one hit when her critical strike chance exceeds 100%.

It’s also worth pointing out that Manamune and Eclipse were recently nerfed, and are no longer good options for Senna. In light of her recent buffs, this three-item core build does the most damage by far.

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