It's not good against control decks, unless theyre running 1-2 cards as the sole and only wincon. Even then, if you run this in the SB, they can just side in more win cons and its again a do nothing card. They have to have 1-2 bullets with no other options for this to be worth it. EVEN then, there is a million ways to interact that can be better than this card. If its a combo deck, then just running a bunch of discard can be better option, because a lot of them need to assemble a critical mass in hand to go off. If its a control deck you can just bring in threats that go under or through contermagic, you can just side into a faster deck and move your decks critical turn to be faster than your opponents. This card is a catch-all designed mostly to allow Crypto to sleep at night in case the format goes up in flames, not to be a staple sideboard card.