Selfless Savior

Protection insurance, folded into a body that also blocks. The lineage here runs through Mother of Runes and Selfless Spirit: white's long tradition of one-drops that stand between your best threat and a removal spell. What separates this design is the currency it trades in. Mother of Runes taxes the opponent turn after turn but demands a summoning-sickness delay and a target color; Selfless Spirit protects the whole team once and asks nothing but the sacrifice. This Dog splits the difference, granting indestructible to a single creature at any point damage or a "destroy" effect threatens it, then leaving play to pay for the save. The instant-speed sacrifice is what makes it live: the opponent can see the shield sitting on the board, but knowing it exists does not defuse it. A damage-based board wipe or "destroy" removal spell still has to eat the sacrifice before it resolves, which turns a one-for-one into a wasted card and forces the opponent to bring a second answer for the creature they actually wanted dead. Indestructible does not cover exile, bounce, or minus-toughness, so the answer it buys is specific rather than universal, and the one-shot nature means it protects exactly once. That narrowness is the price for stapling a bodyguard onto a creature cheap enough to cast on turn one and forget about until the moment it matters. It reshapes how the opponent has to sequence removal, all for a single white mana.