Mana Short is the go-to if you just want to tap out your opponent at the end of their turn, so you can have the next turn free of countermagic/responses
You can later cast the spell from exile by paying its printed mana cost
Robin Hood, Champion of Sherwood usually costs five ink to play but if you already have another Robin Hood card out on the table - such as the new Robin Hood, Beloved Outlaw or Robin Hood, Capable Fighter - then youll be able to play this card for just three ink instead, thanks to its Shift keyword
One such commander is Sai, Master Thopterist, who creates a 1/1 Thopter artifact creature token each time you cast an artifact
Dungeons of Death has a lot of potential if you focus on the two mechanics that Sefris of the Hidden Ways brings as your commander
Subtlety Subtlety is a tempo-lovers dream in Modern