Brooding Saurian

The most quietly disruptive line of text on a 4/4 in any color: a recurring reset that unwinds most theft in the game, fired at the beginning of every end step rather than once per cycle. Control Magic, Threaten effects, a donated Illusions of Grandeur, anything that puts a nontoken permanent under a controller who does not own it gets snapped back at the next end step, regardless of who would rather keep it. What sets the card apart is the axis it polices: it punishes one specific form of advantage (controlling what you do not own) while doing nothing to the more common forms of card advantage. It answers a category of strategy, not a board state. The timing is the catch and the elegance both. Because the trigger waits for the end step, a thief still gets a full turn of value: they can swing with a stolen creature, tap a stolen mana rock, or sacrifice the borrowed permanent to a sac outlet before the return arrives. What the Saurian denies is the long-term keep, not the one-shot use. The symmetry runs both ways, so a deck leaning on its own borrowed permanents has to convert before the cleanup. The body is honest enough to trade in combat while the text works in the background, and the effect resolves on its own each end step rather than asking for mana or an activation, so once it is on the table there is no tax to pay and no window to play around it.