Mono-Red Aggro wants to curve out and burn us down with Burst Lightning, Lightning Strike, and Nova Hellkite, so we need to stabilize the board and protect our life total. Dawn's Truce grants our team hexproof (and indestructible if we promise the gift) at instant speed, letting us dodge a crucial removal spell or combat trick at exactly the right moment. Mossborn Hydra quickly grows past their small burn spells once it picks up landfall counters, giving us a threat that survives their removal suite. Practiced Offense, Icetill Explorer and Poison Dart Frog are cut for being too slow or low-impact against a deck racing to close the game fast; note only 2 copies of Dawn's Truce exist in our sideboard so quantities are capped there.