It can never be opposite day. When ever you say "HEY IT'S OPPOSITE DAY!" the opposite would apply therefor it would not be opposite day. Also if you say "IT'S NOT OPPOSITE DAY!" the affect is not applied.
Great Fur
Extremely Handsome
Innovative Deathrattle
High Level Tactics
Moderately Sized Fedora
Great Animations
Broken Interactions
Must be Weasel Tunneler