Once per turn, during your Standby Phase, you must banish 10 cards from the top of your Deck, face-down (this is not optional), or this card is destroyed
That becomes even more stark when you notice that fourth place goes to Mega Charizard X ex again, but this time in its much more common Ultra Rare form (I pulled one of these, as it happens) at around $57, the other four SIRs following for as little as $30

From the SDCC SDSE-EN001 Jet Synchron SDSE-EN002 Rush Warrior SDSE-EN003 Synchron Carrier SDSE-EN004 Junk Synchron (2 Copies) SDSE-EN005 Quickdraw Synchron SDSE-EN006 Drill Synchron SDSE-EN007 Turbo Synchron SDSE-EN008 Unknown Synchron SDSE-EN009 Fleur Synchron SDSE-EN010 Synchron Explorer SDSE-EN011 Speed Warrior SDSE-EN012 Sonic Warrior SDSE-EN013 Doppelwarrior SDSE-EN014 Quillbolt Hedgehog SDSE-EN015 Tuningware SDSE-EN016 Swift Scarecrow SDSE-EN017 Level Eater SDSE-EN018 Effect Veiler SDSE-EN019 Genex Neutron SDSE-EN020 Genex Ally Birdman SDSE-EN021 Plaguespreader Zombie SDSE-EN022 White Dragon Wyverburster SDSE-EN023 Black Dragon Collapserpent SDSE-EN024 Scrap Fist SDSE-EN025 Limit Overdrive SDSE-EN026 Starlight Junktion SDSE-EN027 Tuning SDSE-EN028 Reinforcement of the Army SDSE-EN029 The Warrior Returning Alive SDSE-EN030 Dark Eruption SDSE-EN031 One for One SDSE-EN032 Night Beam SDSE-EN033 Double Cyclone SDSE-EN034 Scrap-Iron Statue SDSE-EN035 Scrap-Iron Scarecrow SDSE-EN036 Limiter Overload SDSE-EN037 Call of the Haunted SDSE-EN038 Imperial Iron Wall SDSE-EN039 Solemn Warning SDSE-EN040 Stardust Warrior SDSE-EN041 Jet Warrior SDSE-EN042 Accel Synchron SDSE-EN043 Junk Warrior Source: SDCC, Vexacus4666

But most Gruul decks in Commander have plenty of haste, and cards like Bitter Reunion are in Standard, so I can see this card making a new deck archetype