Glimmering Angel

A white flier that pays blue to slip away from the cards meant to kill it: the activated ability folds the multicolor friction of its era into a single clause. Shroud is the whole proposition, a self-protection valve that turns a fragile evasive body into a clock you can guard from spot removal and combat tricks for one blue mana per turn. The protection is genuine because the controller can react: when an opponent points removal at the Angel, you respond by granting shroud, and the spell loses its only legal target and fizzles on resolution. The opponent's real out is to fire the removal in response to the shroud activation itself, before the protection has resolved, so the kill goes off while the creature is still a legal target. The other out is patience: wait for a turn when you are tapped out of blue and cannot react at all. The whole bargain only holds when the second color is open, which is the same tax that priced every gold and splash-cost design of its day; the blue pip has to come from somewhere, and the Angel rewards a manabase already reaching outside white while offering nothing when it cannot produce that second color. Granting shroud as a temporary, color-gated keyword rather than printing hexproof onto the body was still a live idea then, and tying it to a repeatable activation means the durability scales with the depth of your blue commitment. The body never threatens to take over a board; the reason to run it at all is that, with blue up, it outlives the very cards designed to stop it.