Theres no substitute for actually playing your cards and seeing how well they work in games of MTG, and theres no scientific method thats as fun either
This special action doesnt use the stack and cant be responded to, much like activating a mana ability
This is one of those cards which is made worse by looking at the flavour text, which reads: They call it stitchers anaesthesia, a spell to deaden the senses while the mad doctors begin their grisly work. That means that this person is not only alive, but about to be butchered and probably sewn onto a bunch of other people to make a Skaab Goliath or something
Something to look out for as a jump in serialized prices, perhaps
Without first strike, other removal or sac outlets to turn this on you have to use it like a Reciprocate to get a double hit and that is assuming you can get something dead in combat
I proceed to draw mana sources and Pyroblast in the first 6 turns of the game, eventually dying to Show and Tell into Omniscience and Cunning Wish, protected by Veil of Summer and Force of Will