Steel characters, such as Anna True-Hearted, keep your quests safe with high resilience, while items like Imperial Bow give a significant combat advantage, granting keywords like Challenger and Evasive to tip fights in your favor
That land's controller won't get to search for a basic land card
Hopefully, you'll have something much better to do on your turn, but if you're in a desperate spot, you might be able to use the chump blocker and the bonus card it provides to find a way out
Now, a card could conceivably have this effect within the games rules
You can pitch one of your big booty creatures to a sacrifice ability and then get something smaller back to hand
On top of being a great creature on its own (its a mana sink that can deal small amounts of damage to pesky hatebears or other creatures), its a simple way to turn infinite mana into infinite damage at instant speed