Please understand. These are emergent systems that are very hard to spot!
How were we supposed to figure out that people would try to cast two spells a turn alongside Cori-Steel Cutter? We were only testing it in midrange decks with average cmcs of 5+ and it seemed fine.

And Vivi! Do you really expect us to test Vivi alongside Cauldron? That's two cards! How are we, the playtest team, responsible for finding and testing problem combos before they see print, figure out that we have to test the best activated ability ever alongside the activated ability enabler card!?

Please, we are a small team with a meagre billion dollar budget. Please understand.

>Strong cards that leave resources behind when dealt with, like Cori-Steel Cutter and Up the Beanstalk, reliably create that first small advantage. Identifying these cards and evaluating their strength in the context of their interactional requirements is a task that Play Design is incorporating into our process going forward.
SORRY, EXCUSE ME?!
YOU WEREN'T ALREADY DOING THAT?!