For a 5/5 to be that cheap mana-wise, it's more than worth building a deck based around it
It's Birgi herself that's exciting, thanks to her granting you one red mana whenever you cast a spell
You can recur most of your combo pieces with Teshar or one of the retrieving creatures, and some of the available combo pieces can perform double duty as protection, too
Alibou, Ancient Witness Alibou, Ancient Witness Anger Arlinn, Embraced by the Moon Barbarian Class Blur Sliver Cyclops of Eternal Fury Dragonlord Kolaghan Emblem of the Warmind Fervor Fires of Yavimaya Firion, Wild Rose Warrior Garna, the Bloodflame Gimli's Reckless Might Goblin Warchief Hammer of Purphoros Hellraiser Goblin Invigorating Hot Spring Karrthus, Tyrant of Jund Keldon Strike Team Kragma Warcaller Madrush Cyclops Maelstrom Wanderer Maze Rusher Oni of Wild Places Avatar Purphoros, Bronze-Blooded Rising of the Day Samut, Tyrant Smasher Samut, Voice of Dissent Smellerbee, Rebel Fighter Tahngarth Tannuk, Steadfast Second Temur Ascendancy The Fire Crystal Thopter Engineer Tuktuk Rubblefort Urabrask the Hidden Yarus, Roar of the Old Gods
Library of Alexandria ($1,810) Another card where we can start by saying drawing cards is powerful, Library of Alexandria is some easy card draw, especially if you do not mulligan and youre on the draw
