This is important for decks with lots of double-faced cards so youre not struggling with them mid-game, but also relevant if you want to switch sleeves or have an outer sleeve tear and need replacement
These infinite combats can lead to a win or at least allow you to take out any players without blockers
The most common way is the suspend mechanic, like on Search for Tomorrow or Sol Talisman, which lets you exile a card from your hand, put some time counters on it, and then cast the card for free when those counters are gone
There may be many hearts around Emolga in the illustration, but in your heart, there will only be your partner, making this card a perfect fit for Valentine's Day
Players usually get a bonus for this like with Agitator Ant, probably to ease the politics of playing mean goad cards like Disrupt Decorum
A six-mana investment yields a 5/7 butt making it harder to kill with damage dealing removal or in combat