I can easily build a deck that technically meets all the rules of Core (Bracket 2) and plays at the power level of Optimized (Bracket 4), as I'm sure many of you can, too
Kaito, Bane of Nightmares Two generic, one blue, one black legendary Planeswalker Ninjutsu: One generic, one blue, one black (One generic, one blue, one black, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.) During your turn, as long as Kaito has one or more loyalty counters on him, he's a 3/4 Ninja creature and has hexproof
Reliable removal and effectively another modal card
Melvin: My favorite night bonder is my beds pillow
No card in the deck removes that restriction
There are 9 mythic rares, 5 rares, 15 uncommons, and 6 commons with the showcase draconic frame