They're the main players, with some serving as multiplanar Avengers (the Gatewatch), while others want to grow their power and influence across the multiverse
Urzas new planeswalker card is the first of its kind to allow multiple ability activations in one turn, and the first planeswalker to feature five different abilities
Then in your EOT if you have delirium you can exile four or more cards types and drop one to the battlefield with a finality counter
Cloudshift specifically returns the creature to the battlefield under your control, so the creature always enters under the control of the player who cast Cloudshift, where its no longer associated with the mind control effect that originally took it
His deafening voice empowers his ferocious feline allies to claw through enemy forces and crush those who dare challenge his ancient might
If nothing else, its like adding an additional Commander tax for everyone