Aerie Mystics

The defining tension is a white creature whose protective button is locked behind two off-color mana, which makes this a payoff for a Bant manabase rather than anything a mono-white deck reaches for. That gate is the point: it asks you to be running green and blue before the team-wide shroud comes online, so the insurance is paid for in deckbuilding commitment, not just mana. What the shroud actually buys is narrower than it looks, and worth naming honestly. It blanks targeted removal aimed at your creatures, but it equally blanks your own pumps, auras, and combat tricks for the turn, and it does nothing against a sweeper, since board wipes do not target. The sharp use is reactive: hold the mana, then point shroud at the team in response to a spot-removal spell, accepting that your creatures become untouchable by everyone (you included) until end of turn. The flying body is incidental cover for the ability, a way to chip in and survive ground stalls while the mana sits ready. As a design it belongs to a small family of effects that convert a fragile board into a fixed one at instant speed, trading flexibility for a hard, symmetrical answer to single-target removal. The three-color gate is what keeps a repeatable protect-the-team activation from running away: you only get the button if you have built the manabase to press it.