Even if it enters with its base power and toughness, Black Panther can toss on a ton of +1/+1 counters to keep your mana up for other forms of interaction since Black Panther's ability can be done at instant speed
I have actually removed all Tutors from all but two of my commander decks, just because I wanted some variety in play
Now, all of this might seem a simple technicality, because, who in their right mind would play Charizard with no fire energies to make it attack
These are usually unauthorized knockoffs sold on marketplaces and novelty shops
As long as you have one or fewer cards in hand, if you would draw one or more cards, you draw that many cards plus one instead
Research Thief can provide a lot more support, repeatable draw with Constructs, much more then Darksteel Juggernaut