Hymn of Rebirth This one really stood out to me, mainly because it's such an oddball
It might not look like much at first glance, but Delver is so strong that they named an entire deck archetype after it in Magic's cheaper competitive format, Pauper
Then theres the nasty defensive combo of Shelob, Child of Ungoliant plus Arachnogenesis
The silver lining for this effect is that finding ways to recur dead creatures is often easier than lands, not to mention untapping them meaning you could generate absurd quantities of mana
Why would I want to get my cards graded
This card doesn't start in your deck but in a special "Command Zone." You can cast your commander from this zone, and if it would die or be exiled, you can return it to the command zone to be cast again, though it costs an additional two mana for each subsequent cast