Stoic Angel

The static lock here is a Winter Orb pointed at combat rather than mana, and its asymmetry is the whole design. Capping each player at one untap per turn does nothing to the player who attacks first: the player on the wrong end of the clock has to choose, every turn, which single creature gets to be available next. A board of blockers becomes a board of one blocker. The Bant color identity matters to how the piece is built: green and white supply the bodies, blue supplies the patience, and a 3/4 flier is exactly the rate that punishes a stalled board. The wrinkle is that the lock hits its own controller too, which is why the vigilance is not decoration but load-bearing. Because vigilance lets the Angel attack without tapping, it stays available to block regardless of the untap tax it has imposed on everyone: it never has to spend its single permitted untap on itself. Play it ahead and it reads as a soft prison-clock; play it behind and you have handed the opponent a tempo machine while still owing the same untap restriction yourself. That self-targeting symmetry, resolved only by the body's keywords, is the reason this never became a generically good creature and instead a tool for decks already set up to exploit a grinding, one-creature-at-a-time game state.