The enter + attack triggers exile nonland cards from players' decks for you to try and play later
That isnt to say it cant support tokens, landfall, or other specific strategies, but what Simic does best is generate huge amounts of mana and give you creative ways to spend it
Flying might be distinctly weaker than the cant be blocked text on cards like Slither Blade, but its hard to think of a more iconic evasive keyword
The result is a deck that feels cohesive, with every spell or permanent working toward the same game plan
It wasnt too long ago that one of the defining characteristics of Standard was the smoothing provided by the ten Temples that let you scry 1 when played
Once it's cast, you can't change its mode, even if creatures' powers change in response