From a strategic standpoint, slivers have never been the most complicated creatures in Magic, and in a lot of ways a sliver deck ends up playing itself
Using a card like Lost Legacy to chew up your opponent's crucial cards like lions or clowns at a carnivorous carnival can be a complete cannonball if cast at the correct moment
Mizzix of the Izmagnus, the new Gandalf the Grey or Saruman, the White Hand, Niv-Mizzet, Parun and his counterparts, etc.) or Burn spells (Solphim, Mayhem Dominus, Urabrask // The Great Work, Aegar, the Freezing Flame, etc.), odds are Immolating Gyre will have plenty of cards to count by the time you hit six-mana
Selling: Should you wish to sell your shiny new graded card, leverage platforms like eBay, specialised forums, social media groups, or local collectible/TCG shops