Not too hard to accomplish with a green strategy
Don't let your vision remain a concept
Siege-Gang Commander is a great card, but every great commander is only as good as their lieutenants
Eventually we assemble a combo like Vadrik, Astral Archmage + any R generator like Storm-Kiln Artist + Searing Touch for infinite damage, or Electrodominance copied with Reiterate (w/ buyback) for infinite damage
The front face simply provides you card advantage if you have enough double-faced cards, but the back face, Gargantuan Slabhorn , is perfect for protecting your bigger, smashier double-faced creatures
This goes double for the Enchanted version, which depicts an unusually intimidating version of the character well, as intimidating as he can be, which still isn't all that much