Law and Kid have been groomed by Oda to defeat Big Mom but it does not feel remotely earned, believable or satisfying. Going into the fight both have defeated a grand total of zero commanders and have zero feats to suggest that they are remotely, justifiably able to take down a Yonkou. And what is Oda's solution? One of the most mysterious powers in the series: devil fruit awakening. Said to be the product of devil fruit mastery is just given to them both at the same time randomly, off screen. Introduced with a line of dialogue equivalent to "hey bro you awakened?" "Yeah I am bro".