Rules Help: Ratadrabik and casting X=0 | tcgmode

I’m building a \[\[ratadrabik of urborg\]\] commander deck and am looking into how X costed legendary creatures work. Assume ratadrabik is on the board. Can I choose to cast \[\[omarthis, ghostfire initiate\]\] for 00? Would he enter and die and rata the make a 2/2 Zombie copy token? Thanks!