mtg cards in graveyard gain flashback Snapcaster Mage (Regional PTQ) [Pro Tour Promos] (You may cast that card from your graveyard for its flashback cost Sphinx of Forgotten Lore

Check Lands Any dual land that can enter untapped on a regular basis is a pretty good option for mana fixing in Commander

Warrior's Oath and friends give you a Time Walk, which we all know is busted, but you lose at the end of the extra turn

Besides being a great addition to any control deck , Thalia is also an easy-to-cast three mana with one color symbol, and she can take down a three-toughness-or-less creature without having to trade

All by itself, a 2/2 with vigilance that can tap for two mana is already borderline playable in Commander, but in a deck with three or more colors the card just gets bonkers

You can try and build around them and turn it into a Voltron commander, but limiting your options to do this with a red commander might prove challenging

Stitch In Time is a 3-mana Time Warp with a 75% success rate with Krark's Thumb