Many BK players go close and personal with fernando since they think they can blow him up ( ͡° ͜ʖ ͡°). While that is true, fernando has a weapon that is great for pressure. And a pressured BK will go bonkas. Maybe even blow himself up( ͡° ͜ʖ ͡°)
What seperates good BK players and bad BK players is their timing of their bombs. If you see a noob BK missing all his shots, try to pressure him and kill him. But be careful! Many (noob) BK's will panic and use all of their abilities to kill you.
Having trouble using your ultimate? Try to use poppy bomb first and then immediately king bomb (Ultimate), this will make you faster than a max speed maeve, so the enemy wont even bother trying to kill you while you're trying to give them a big hug.
USE YOUR WALL! It blocks fatal attacks, (Terminus ult, skye ult, ruckus ult, willow seed, BK grumpy, etc...) Most healers need line of sight to heal. block vision from a single target with your wall and burst them down before their healer can react