Like Magic: The Gathering Arena, the free-to-play app features an economy built around gems that can be acquired through play or via real-money microtransactions, before being spent on virtual packs, a timed duel pass for unlocking bonus items via ranked play and accessories such as companions, card sleeves and battlefields
If this face-up card would be destroyed, you can detach 1 Xyz Material from this card instead.
If this card is Normal or Special Summoned: You can Special Summon 1 "Nordic" monster from your hand
Each time a "Trickstar" monster you control inflicts battle or effect damage to your opponent, inflict 200 damage to them
And its basic attack, hilariously entitled "Eeeeeeek", lets you shuffle your hand into your deck, and draw seven new cards
This can really cripple decks that rely on specific card effects too, like Vampire Sorcerer or Vampire Vamp in a Vampire deck