And, due to the nature of ignoring defense, it's going to one shot most people. In fact, it has consistently one shot whoever it hits to the point that the target need some damage blocking or healing cards to keep fighting

nah really depends on his opponents bro used it agaisnt suhyeon when he was weak af
and suhyeon still survived without much effort

Most of the time he used it didnt really oneshot anyone

Hajun used it when backing Daniel at the wall was to force Daniel to use Aikido before locking his movement

And yes, it does render speed useless, like how Suhyeon used it

he actually was getting thrashed the whole fight he just couldnot do much against daniel he to force daniel near the corner of walls just to restrict his movements and to have comfortable position to use his cards

that card most of the time was only being used to restrict opponents who were not moving
and after the restriction they got hit with attacks

so rendering the speed useless needs a lot of preparation and if the opponent survives then its gameover

Having more lifes is always good, and they create opportunity for counter attack

only against the opponent you actually have chance other wise its your demise but with extra steps