The Human Skeleton rammed his head in Zayn's direction. It was a sudden movement, which made it near impossible for Zayn to react in time and evade it.
'Too fast!'
Zayn grit his teeth, trying to put the silver iron shortsword between himself and the Human Skeleton. However, he was clearly too slow which was enough to come up with a quick defensive technique. Thus, he forcefully circulated soul particles through his entire body in an attempt to strengthen himself.
He was still too slow and imagined how his own skull would crack the moment their heads butted against one another. Just as Zayn grit his teeth and prepared himself for the inevitable the Herculean Human Spirit jumped in between Zayn and the Human Skeleton at the last possible second.
There was not enough space for the Herculean Human Spirit to squeeze in completely but it was possible for it to intervene by altering the trajectory of the iron mace's smash.