Donald Trump’s recent comments that Mexican immigrants are “rapists” and “killers” have led a growing number of his business partners to sever their ties with him. Macy’s, NBC, Univision, ESPN, and now the Professional Golfers Association have all dumped him in recent weeks.

Trump’s response to his critics has been to go on the offensive. He’s threatened to sue many of the businesses who have ended their relationships with him. And the controversy over his comments doesn’t appear to have hurt his presidential prospects. He’s still rising in polls in early primary states.

Who will incur The Donald’s wrath next? Here’s a guide for those seeking to annoy the famously thin-skinned Trump:

Talk about his financial worth: Trump’s net worth has been a point of contention for decades. Forbes dropped him from its list of billionaires in 1990, and he nearly declared personal bankruptcy in 1990. Reports of his wealth have fluctuated wildly, and Trump has countered many of them by suing and threatening to sue for libel. He called suing The View's Rosie O’Donnell “fun.” When he declared his presidential candidacy last month, Trump filed papers claiming he’s worth $9 billion.

Build a wind turbine: Trump had a years-long battle with the Scottish government over plans to build an 11-turbine wind farm near his golf resort, which would spoil the view from the course. He accused officials of having an illegal bias in favor of the project. When a judicial panel threw out his lawsuit in June, it looked like he lost his case. And yet, Trump still won in the end—not because of his own challenge but because local environmentalists convinced the court that the turbines would hurt a protected species of mussels.