Godsend

Commander is where Godsend does its best work — repeated combat over a long game means the exile clause fires often, and white's historically thin permanent removal makes every extra exile effect meaningful. In 1v1 formats like Legacy, Modern, and Pioneer, Godsend is three mana to equip onto a creature that may never survive to attack, which makes it too slow against anything proactive; the payoff requires a board state that those formats punish you for assuming you'll have. Oathbreaker sits closer to Commander on the speed dial, so the card is at least functional there, but the 20-life clock compresses games enough that you rarely get multiple combat steps to justify the investment.