Its cheap but not overpowered since it does nothing if the threat is already on the board and is never better than an even one-for-one trade
Azorius Control (1 player): This deck controls the game with spot removal like Prismatic Ending, countermagic like Counterspell, sweepers like Supreme Verdict, and planeswalkers like Teferi, Time Raveler
Edric, Spymaster of Trest Edric, Spymaster of Trest is a classic extra turns commander
Infinite Guideline Station Now that legendary vehicles and spacecraft like Infinite Guideline Station can serve as your commander, this quirky artifact is even more exciting
Lolth and The Wandering Emperor also join the fray as sticky threats that just accrue value for you over time
The picture of the card Serendib Efreet was mixed up with Ifh-Bff Efreet