WotCs R&D always receives questions about when youre going to complete said cycle. As an example, we can cite the 1-mana tutors that tutor for a card and put it on top, like Vampiric Tutor, Worldly Tutor, Enlightened Tutor, and Mystical Tutor, lacking the red one
Which behaves like a parasite .It's a bit of a mouthful there, but essentially it keeps subtracting the maximum toughness of creatures, and when they die, it moves on to another creature and ultimately to the player
Of those who tried in the past, no one really got it right
I touched on it recently in my piece about how people should be running more and expecting more graveyard hate
16 Shu Yun, The Silent Tempest Strike Hard, Strike Quiet While Shu Yun, the Silent Tempest is a blue creature, due to the Boros hybrid mana cost within its triggered ability, Shu Yun functions as a Jeskai commander
Token decks will happily slot this in