This five-mana red and white planeswalker comes in with four loyalty, can create 3/2 spirit tokens, allows you to Discover with a value of four - which means you can cast the next nonland card in your library with a mana value of four or less for free - and lets you exile cards from your graveyard to gain mana, then cast those cards if you want to
Honorable Mention Emberwilde Captain Emberwilde Captain is a strong, aggressive threat stapled with card advantage
The Corsair Captain (a 2/2 Human Pirate card) generates a Treasure Token and adds 1/1 to all other pirates the player controls
You also get to untap six lands after casting it, making Time Spiral essentially free, or even better, giving you more mana than what you started with
Ultima destroying all artifacts is the ultimate nonbo with this card, so unfortunately you can't play this amazing wrath effect if your deck also relies on Pinnacle Starcage