In a Two-Headed Giant game, Elesh Norn does not affect triggered abilities of permanents your teammate controls
Flare of Fortitudes great strength is the unexpectedness: You can freely tap out without worrying about dying on your opponents combat step
Being able to completely wipe the entire board of any nonland permanent is ridiculous in a format like Commander and Miku, Child of Song will not hold back any mercy if you face her as a commander
At the end of a player's turn, they untapped all of their lands, giving them most of their mana sources back for the other player's turn
In addition, Aethersphere Harvester has Crew 1, requiring you to tap any number of creatures you control with total power of one or more to turn Aethersphere Harvester into an Artifact Creature until end of turn
You might find this card for less than $10 on third-party marketplaces, so if you don't pull it yourself, it might be worth a pickup