digimon card agumon [ST5-03] [Starter Deck: Machine Black] with detailed artwork on an uncommon card. Digimon Trading Card Game Sinister

Most of the time this is immediate, as the effect that caused the trigger has finished resolving and the game checks to see what triggered to put it onto the stack

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

Value Cards: Aminatou, the Fateshifter Yuriko, the Tigers Shadow Sower of Discord Ponder Aminatous Augury Forge of Heroes Sower of Discord is a unique effect and hasnt been reprinted in the years since, hanging in at $11

Luckily, there are some trading approaches you can use to mitigate this