Agrus Kos triggers, so pay 1R/W to copy Soulbright Flamekins ability for each other creature we control
(Plus Merlin, Shapeshifter in his own human form.) Each of the shapeshifting Merlin cards offers a different boon when they first arrive on the table and when they leave, presenting the opportunity to combine them with cards that cycle them in and out of your hand to stack up the benefits
For example, the Simba - Future King card is different from the Simba - Returned King card, so a player could have four of each card in their deck
As for booster draft, some enemy decks are too fast and aggressive for cards like this, so the player must be prepared to side out Virtue of Persistence if need be
Both are also four-drops and they'll get any Swamp, even a dual land, but this is key in Black decks alongside Cabal Coffers and Cabal Stronghold and similar massive ramping from your Swamp count
Either you dont do a good enough job and you become borderline irrelevant, unable to keep up with the proactive engines of other decks
