When his spread lasers happen it seems almost impossible to dash through them and not get hit.
Tips on Beating Gigald (Final Boss) on New Game Plus (NG+)
I find the most success by moving just a little bit to make it easier to avoid the blue lasers that like to spawn on top of you, but not so much that I run headfirst into the pink lasers that scissor you. Other than that, you may want to grab one or more levels of the mushroom relic to improve your dash uptime.
A couple of Fruity Bush contraptions are handy to keep around.
If you have a couple of fruity bush’s and a fairy you should be ok, easy to lose your fairy just before the king though. ng+2 king is a real ***, I’ve only managed to get there with the vampire dude, I manged to take about 3/4 of his first health bar down. I sometimes use a demonic grave stone that gives you a temp demon for a hero soul, if I start to panic a bit too.