Ask anyone about what they think about Mindless Null, and you’ll probably get a response of “.....what?”. But ask any Magic player, and the best case scenario is them deriding it. Worst case you get a half an hour tirade that somehow ends on the current state of the world.
But in 2009, Mindless Null was included in Zendikar nonetheless. And that was even then people knew it was going to be a mistake. And by people, we mean Wizard’s R&D team.
A big part of the issue was its converted mana cost: It was two (1B). For a simple blocker card that specifically relied on other cards and could not be played easily. A more tolerable card would have used one mana, which as it turns out, was originally the case.
R&D originally had it set at one generic and a black, but after Ken Nagle dropped them off, another designer put it in as two and a black. When it was noticed, R&D somehow thought this was hilarious and one of the most hated Magic cards ever was created.
There was even a fight over this. Mark Rosewater himself thought the card was as weak as Scathe Zombies way back from Alpha, but was outvoted simply because everyone found it funny.
Next time you’re wondering how a card could be so bad, consider for a moment that it was accidental or that they thought it would be a good idea based on no-basis. And because Rosewater has stated he’s all for making worse versions of current cards, we’ve slowly seeing more of downgraded cards. It's not a well-liked trend and it all started because somebody put a two in instead of a one.