Qasali Pridemage will do the trick by itself
Think two Hopeless Nightmares, or maybe two Momentum Breakers, to deal with big creatures or take their cards
Plus, I want to build a deck with lots of new and exciting Oath of the Gatewatch cards
Its great with commanders like Rashmi and Ragavan that only trigger once per turn
In these midrange mirrors, it makes engaging in combat in any way nearly impossible for your opponent whilst it is sat on the battlefield and as a result ends up being a removal magnet, drawing you a card in the process and meaning that your more expensive creatures stand more of a chance of surviving
However, if you want to try this ninja out as a commander, you can add Arcane Adaptation or Maskwood Nexus for creature type fixing