Uh... internal energy is a precious thing. Like a teacher gives it to his prized student or one person gives it to his lover. There wasn't enough justification for two sect leaders to give it to ML. Maybe if it was the end of the world or there was a strong enemy. This is deus-ex-machina
& they introduce them like they're gonna be very important in the story and bam the next moment they die 🤣
Yeah. Even if they are going to die later, they should be properly introduced and then die like after 2-3 eps. The way this drama is using its supporting cast is like Star Trek and its "Red Shirts".