The plane of Dominaria was the birthplace of the shadow mechanic, so maybe well see shadow again on a return visit, but its a fairly small possibility because R&D avoids putting parasitic mechanics (i.e., mechanics that only work with themselves) in modern sets
If you are a TCG (trading card game) collector, there are special cards known as Immersive Cards that are the #1 hunt for most because of their high rarity and immersive animation
Phyrexian Swarmlord #119 New Phyrexia Change Version Phyrexian Swarmlord Creature Phyrexian Insect Horror Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) At the beginning of your upkeep, create a 1/1 green Phyrexian Insect creature token with infect for each poison counter your opponents have
It sniffs and snuffles around, looking at the long faces of the Magic players who were promised that Magic 2010 would be a set with all new cards, only to find out that many of them were merely renamed cards such as Runeclaw Bear and Divination
Cards you can only obtain 1 or 2 copies of in-game can only be included up to that number in total across all Decks