Luo Yi

In teamfights, use Luo Yi's 1st Skill to mark the enemy with a Yin/Yang Sigil and use it again on another nearby enemy to apply the opposite Sigil and trigger a Yin-Yang Reaction. Then repeat the process. If there is only one enemy, use Luo Yi's 2nd Skill to trigger Yin-Yang Reactions.

In the laning phase, use Luo Yi's 1st Skill to mark the enemy with a Yin/Yang Sigil, then use her 2nd Skill to summon Fire of Yang or Aqua of Yin in range of the target to trigger a Yin-Yang Reaction.