Generally speaking, the iconic creature types in MTG are: That split is also why Iconic Masters confused a lot of people: The set name sounded like it would be all about the most historically famous cards, but the theme was largely about those iconic creature types
If Golden-Tail Trainer's power changes after costs are locked in, or if Golden-Tail Trainer leaves the battlefield while you are activating mana abilities or paying those costs, the cost reduction effect won't be affected and the total cost to cast the spell won't change
Every conspiracy card is permanently banned in every Constructed format
As one of the strongest Sultai cards it still sees quite a bit of play in Vintage and Legacy, the only other formats where you can play it
There are some great cards like Open the Way, some subpar ones like Entrancing Melody, but there's a serious omission of the ultra-powerful haymaker X spells, the game-enders, the good stuff