I honestly velieve this card is amazing in firekings nephtys. The fact that it os an engine that unbricks itself and reliably goes +1 is actually unheard of. Let's take an example with another plussin engine, the venus engine. It has a reasonable cap at +1, has a high chance to brick with multiple shine balls in hand and has not very much power. The new fireking engine can of course brick as well but since this deck has a way more diversified search potential with card of soul,pathfinder, island and now trooper makes the deck less reliant on restart and leaning more towards beatdown which will make the deck tier 0 in my opinion
Tier 0 is deck with 50% play rate in the meta. For duel link, I think we could count deck percent of ppl reach kog for that, but I dont think anyone could do this survey.
Going by textbook its >65%. Anyway tier 0 is a deck that is so OP it basically have no real counter to the point of people can only run that very same deck to possibly win(reach KoG in this game). The rest are just deck that tried to counter it(and fail) and memer. Nephtys with this card definitely won't reach that. Its still slow, weak to grave removal, have hard time against real BIG mons, etc