"Outlandish behavior" refers to actions or conduct that is peculiar, strange, or eccentric compared to what is considered normal or socially acceptable. Full definition
We make much of the excesses of the empire, note the orgies and vomitoriums, the bread and circus to entertain the mob, and the strange and outlandish behaviors of the rulers. (policygenius.com)
YouTubers, who chase clicks with outlandish behavior, aren't just catnip for kids. (usatoday.com)
2) Mealtimes are ridiculous with throwing and other outlandish behaviors. (rookiemoms.com)