This feeling is real... I'm more worried about how my characters heads and body design than anything. I'm good at character and story writing than character design. 😢
That wasn't a nuke... way too much energy dispersal and the Shockwave stayed under water. It didn't get turned into a steam bath... so it wasn't thermobaric... That energy pulse... I'm going to go out on a limb and say it's either Antimatter or something exotic tied to a primer like a bulk charge.