User blog comment:Battlefan237/Battlefan kicks out the Halloween parade ! Kayako Saeki vs. IT/Pennywise the Clown/@comment-3189283-20181001125254/@comment-28716800-20181002100300

Mutual destruction would be the best term to describe Kayako vs Sadako, though, because both of them perished in the explosion and combined into a new entity later on. Thanks for the great vote.