I consider it a one-shot and have never thought of it as anything else other than he is breaking the fourth wall to use the keyword box as a weapon.
We just reckon he really broke that wall, and broke the card while he was at it. HEY BUSTER. YOU DON'T TALK LIKE THAT TO MY CARDS. Guise deals one target 3 damage. HEY GUESS WHAT IT'S YOU.