Little Borden's will!
If Quinn was to place a bet on the first human he would have run into on this island, it would have never been little Borden. Although human wouldn't have been the right word to refer to him. Especially after witnessing something completely inhuman.
Something the size of a puppy had just knocked aside a huge black cat that was bigger than a tiger with a single punch! At the moment Borden didn't really look human either, he was in a form that they had seen him in only twice. Once, when Quinn had first met him as a single Spiked Dalki, and later on when he tried protecting his brother as a two spiked Dalki.
Judging by the blow he had delivered to the King tier beast just now, it seemed like even in his small size, with the two spikes sticking out of his back, he was just as strong. The only difference was his size which might be an advantage in some situations.