Combining Mogis with a card like Blood Artist would allow for a player to ensure their opponent loses life every turn, and they consistently gain life making the game an uphill battle for their opponent from the moment Mogis hits the battlefield
If you want to go in another direction, and many players in lower brackets do, The Ghoul is a superb Zombie Commander to mill yourself and find recursive undead like Krovikan Horror, Bloodghast, Ichorid, etc
Also, with cards like Wishclaw Talisman, the downside of donating the card might be obviated by you using the card to win that turn
2 Blue Fairy, Rewarding Good Deeds Having more cards usually means more wins, a common refrain heard in any TCG
So even if we dont flip the attacking creature, it at least has a better chance of survival, or doing more damage, as a 5/5