Austere Command is far less restrictive on your own build than other six mana mass removal
Be'lakor was the first Daemon Prince the Ruinous Powers brought back, and he's first in our hearts as Magic 's greatest Demon lord
Second Pro Tour
Notably if you can get this creature onto the battlefield without casting it, for example reanimating it from your graveyard, you wont have to sacrifice a creature

Ancient Silverback Arborback Stomper Back for More Back for Seconds Back from the Brink Back in Town Back on Track Back to Basics Back to Nature Back-Alley Gardener Backdraft Backdraft Hellkite Backfire Backlash Backslide Backstreet Bruiser Backup Agent Backup Plan Backwoods Survivalists Barbed-Back Wurm Beetleback Chief Bladeback Sliver Borough Backup Brambleback Brute Bristling Backwoods Brought Back Burdened Stoneback Casey Jones, Back Alley Brute Chaotic Backlash Charging Slateback Come Back Wrong Daggerback Basilisk Dismal Backwater Dragonback Assault Dragonback Lancer Essence Backlash Feedback Feedback Bolt Feral Throwback Flashback Gnarlback Rhino Granny's Payback Green Goblin, Back for More Grim Backwoods Gristleback Hamletback Goliath Hangarback Walker Isleback Spawn Lathnu Sailback Leatherback Baloth Marketback Walker Nurturing Bristleback Orazca Frillback Parallectric Feedback Phantasmal Shieldback Ponyback Brigade Pygmy Razorback Rattleback Apothecary Ravenous Sailback Rubbleback Rhino Saddleback Lagac Sangrite Backlash Sawback Manticore Scuzzback Marauders Scuzzback Scrapper Scuzzback Scrounger Shadowy Backstreet Shamble Back Silverback Ape Silverback Elder Silverback Shaman Skyshroud Ridgeback

Printing cards like Seasoned Pyromancer, Wrenn and Six, Ragavan, Nimble Pilferer, and the like in the way it does currently (at mythic, in sets that aren't limited in supply but have an abnormally high price point of double or more a typical Standard-legal set) all but guarantees they will be incredibly expensive, increasing Wizards ' reprint equity