I had my entire table crash out over this card. am I right?

1. This can block unblockable creatures
2. This does not 'declare blockers', it's entered blocking like 'tapped and attacking' triggers

A token created by Mirror Match will be blocking the creature it’s copying even if that creature can’t be blocked or has an ability that would stop the token creature from blocking it (such as menace or protection). This is also true even if the token creature has an ability that would stop it from being declared as a blocker.
(2015-11-04)