It's fair to say Wizards of the Coast dropped the ball with Companion, which lets you play with an eighth card in your hand, provided you meet restrictive deck-building requirements
Honorable Mentions: Playtest Cards Both of these playtest cards have cheeky references to scrying, but they're obviously not legal anywhere
In the late game, if the life loss from the upkeep trigger starts to become a liability, you can use the Bearer as a chump-blocker or shrink it away using a Blight cost to save your life total
Heavily Played condition cards may include cards that have significant creasing, folding, severe water damage, heavy whitening, heavy border wear, and/or tearing
Killing something on the way in is already appealing, and making the next Karn token enter the battlefield tapped ensures Karn is at greater risk on your next turn