How many minutes it took for you to transform like that while all your opponents stared in awe and fear?
Also, everybody stop being so silly, it's just a yukkuri imagining itself powering up, in reality she's probalby just puffing up or something, we had pics that confirmed this, it explains why yukkuris keep on using puff up when it's so blatlantly useless, they are literally delusional about "powering up" while "puffing up".