A 2 mana instant that can draw you two new cards is the perfect thing to cast at the end of your opponents turn in which you did not need to counterspell anything
When your opponent activates a card/effect that would add a card(s) from their Deck to their hand while you control a "Reshiram, Dragon of Truth" or a Fusion Monster that lists it as material: Negate the activation, and if you do, destroy it, then if this card was activated from the hand while revealed, your opponent discards 1 random card
This is the first printed language in which there is no form of text about the Attributes
40 lands might be a few too many, given the mana sources elsewhere in the deck, but this can always be addressed with a few upgrades
That'll backfire on legendary creatures, unless of course, they have a relevant enter-the-battlefield trigger