About T-Shirt Design
You do not have to think too hard about RUB LUCK T-Shirt. The joke is right there and it gets the point across fast. It has a clear St. Patrick's Day vibe, which makes it easy to picture as a gift or something to wear for fun.
You could wear it for parties, bring it out for parades, or just keep it in the normal shirt rotation. It has that sarcastic t shirt attitude people like when they want something a little more blunt.
It fits nicely with novelty t shirts that are meant to be fun first and serious never. The design is easy to get, easy to gift, and easy to wear without overthinking it.