So for example, Mikus Spark reprints Chandras Ignition, Miku, Lost but Singing is a reprint of Azusa, Lost but Singing and Miku, the Renowned repurposes Feather, the Redeemed
There are plenty of ways to make it happen, however, whether its just playing creatures with Flash or bringing in creatures via Ninjutsu abilities
Light test: genuine cards show a dark core layer when held to bright light
It can declare rulings on any in-game circumstance, issue errata, change card text after publishing, and change the basic game rules, although the latter three rarely occur
Otherwise, put it into your hand. Putting a card into your hand is nice, but you can literally win games by just combining Meren with Spore Frog, which you can sacrifice to prevent all combat damage for a turn - and only costs one mana