Talk:Pantheon/@comment-5686533-20131102214618/@comment-5955640-20131103184715

"If Heartseeker Strike has been leveled up once, Spear Shot will "crit" against targets below 15% of their max health, dealing 50% more damage. Bonus critical strike damage from other sources are also applied."

After getting the passive your Q can crit. When it crits it triggers the frenzy mastery seeing as the frenzy mastery does not say that it has to be triggered with auto attacks that crit.