9 Zhulodok, Void Gorger An Eldritch Terror An absolutely ridiculous commander, Zhulodok, Void Gorger takes all your colorless spells that you cast with seven or more mana and lets you cascade twice from them
Sticking to two colors also makes it slightly easier to establish your land base and more reliably get cards out quickly
When it connects, you have to Convert it to Blitzwing, Cruel Tormentor
For the sake of this list, Energy Counter Commanders will mean any Commander-legal legendary creature that mentions energy counters or synergizes well with them
In theory, you can also dip into +1/+1 counter strategies to buff your creature tokens, then copy those using Populate, further increasing those lifegains
To add to the, uh, mystery, there are two versions of Mystery Booster a Convention Edition that will be available at MagicFests and conventions moving forward, including PAX Unplugged in Philadelphia, Dec