We went back and forth on this during design. Should minions with “Can’t Attack” be allowed to attack? 0 Attack minions? Frozen minions? You could make arguments for each of these. Ultimately, it came down to Supercollider - we use the same wording for both and we wanted these two weird cards to act similarly. For Supercollider, the story is that you’re smacking two minions together, so Frozen, Can’t attack, and 0 Attack minions should all get smacked into an adjacent minion. So we made Mass Hysteria the same. As a bonus, it seemed simpler and there were less edge-case if we said it worked on all minions.