Armored Guardian

The double-pip activations are the whole tax here: white-white buys protection from a color for any one of your creatures, blue-blue makes the Guardian itself untargetable for a turn, and both grants demand you commit hard to your colors to keep a single body alive. A 2/5 that does nothing the turn it lands was never built to swing a clock; it was built to survive. The toughness exists to make those activations recurring rather than one-shot, surviving combat and sweepers long enough to keep paying its own upkeep. The first ability was the more flexible weapon in its era: protection from a color answered combat math, color-based blocks, and a swath of targeted removal all at once, before instant-speed answers grew cheaper and cleaner. The second ability is the narrower, more defensive piece, shrouding the Guardian against spot removal and theft auras alike. Together they read as honest color-pie work: protection grants are white's province, untargetability is blue's, and this just houses both behind a wall of toughness. The design is a clean snapshot of what Azorius meant in its earliest two-color outings: protect what matters, refuse to be answered, and win slowly while the opponent runs out of ways to interact. It is a defensive linchpin for a control shell, a role white-blue would chase for years afterward with tools that asked for far less mana up front.