Since it can target creatures as well as players, you can use Undying Flame to slowly get rid of all the creatures on your opponent's battlefield
Because of this, a card requiring two mana is almost a dealbreaker, and one is more than you want
Consider these Commanders from Magic: The Gathering's Transformers collaboration In a never-ending attempt to reach all corners of pop culture, Magic: The Gathering and its Universes Beyond enterprise have finally given us some Transformers , albeit in collector boosters of a Standard set The Brothers' War
Eight lands in play is the break-even point where you can cast this for free, though you could always run it out earlier, hope it sticks around for a turn cycle, and untap with something like 10 to 12 mana from lands alone
Glimpse the Core Remember when Dominaria put Llanowar Elves back in Standard