Path of Bravery

The two halves of this enchantment are wired to run in a loop, and the wiring is the whole design. The anthem is conditional: your creatures get +1/+1 only while your life total is at or above where you started, which is exactly the threshold a go-wide aggressive deck threatens to drop below the moment it commits to attacking. The combat trigger repairs that. Every combat, you gain life equal to the number of attackers, so the act of swinging with a wide board refills the life total that the act of swinging put at risk. A token-flooded board attacks, gains a fistful of life, stays above starting total, keeps the buff, and hits harder next turn. It is a positive feedback engine built entirely out of the player's own aggression, which is an unusual thing to ask of white: most lifegain in the color is defensive, a tax on tempo, whereas this turns lifegain into the fuel for it. The catch is the same conditionality that makes it sing. Take a single bad combat or eat enough burn to fall under your starting life and the anthem evaporates; the trigger keeps gaining you life unconditionally, but climbing back over the line takes a board big enough to do it in one swing, and a deck that fell behind rarely still has one. It rewards the player who was already winning and offers the falling player only a partial lifeline, which is a sharp, honest way to price an effect this snowbally.