The first aims for an inexorable long game, carefully timing blink spells to safely reuse ETB effects, often countering single target removal or turning evenhanded board wipes into events where you come out far ahead of the rest of the table
Blackmail does scale well with other discard more so than most and as such I have played it in Rack themed black decks before which want a heavy number of discard cards
This ability will put another Zombie on the battlefield and it will both make my Zombies stronger and will make sure they have a power greater than their base power
Finally, lets talk about the xx/77 Golden Chocobos
Still overall a weaker Psychic Corrosion for multiplayer formats, which isnt especially powerful itself, so unless youre all-in on drawing cards, Id rather look elsewhere
Would you ever play this on the first turn