As he has done in years past, Kentucky Republican Sen. Rand Paul on Saturday participated in a humorous “airing of grievances,” a practice popularized on the television show Seinfeld.

Characters on Seinfeld celebrate the parody holiday “Festivus” by airing grievances with each other.

For years, Paul has been tweeting his grievances, and on Saturday, he took aim at President Trump, former Democratic presidential nominee Hillary Clinton and joked about a recently revealed Pentagon program to investigate UFOs at Harry Reid's request.

“You’re going to be saying #HappyFestivus again,” Paul tweeted Saturday, channeling Trump. “Believe me!”

Here are some of Paul’s grievances: