If anyone doubts how much Doriki is produced by Bigan:
Hakified Santoryu Zoro isnt pushed back by King's Zoan slamming into him.
Hakified Santoryu Zoro is pushed back significantly by Bigan:
Can Lucci produce higher Doriki than King's slam?
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Never underestimate the horsie.
Kaku, around 10 times more. They cant even be compared.