If you only have one opponent and you attack them, there are no other opponents to create tokens for
But even if you do not want to plan your whole deck around Behemoth K, he is just strong card in general and will be included in many Lightning-Decks for sure, especially since you can search him with [10-086C] Aldo, [9-063L] Gabranth, [11-072R] Tyro and another Card in Opus XIII: Crystal Radiance I also like the idea of running Behemoth K in an aggressive Lightning-Deck with Cards that constantly treating your opponent and trying to deal 7 points of damage very quickly
In Vintage, Mana Vault is a great mana accelerant for Paradoxical Outcome, which can reset the Mana Vault, allowing for additional burst of mana in the same turn
one in an indicated color, and the other a random one of the other four colors in Magic
Its everything I want to do in Peasant Cube
Of the three, my favorite design is the first, since getting a benefit for casting a spell from outside your hand creates an incentive to find wacky interactions