When checking the EDHREC website for these previous cards, we find that they are often used with commanders that have exponential effects, like Heartless HidetsuguHeartless Hidetsugu or Zada, Hedron GrinderZada, Hedron Grinder
Triggering the Meld mechanic exiles the pair of cards, bringing them back onto the battlefield as one card with both pairs flipped over
Of course, you must still clearly indicate which card you are moving from your discard pile as that zone is open to all players
Standard was a place where flexible five-mana cards could remain on the battlefield and accrue advantages over time
Omnath, Locus of Creation Change: When Omanth enters the battlefield, you Scry 1 instead of drawing a card
Special Illustration Rares appear in less than 1% of packs