Andrew Caballero-Reynolds/Getty Images Europe

Kirk Hammett, who joined the American heavy metal band Metallica after Dave Mustaine‘s kicked out in 1983, has celebrated his band-mate Lars Ulrich‘s birthday and stated that he is his ‘musical mischief partner’. In the photo he shared, Kirk joked Lars Ulrich and said do not eat too much cake. He also said something to him in a language we don’t know what it means.

You can read what Kirk wrote for Lars Ulrich’s birthday celebrate below.

“To my musical mischief partner in crime and in all things under the sun, Larzy Poo – all the best of days bro, can’t wait to start fuckin shit up again, hope you have a GREAT day, don’t eat too much cake!!! Much love and Aloha, Musa kusa fisa, tak!”

Here’s the birthday photo Kirk shared for Lars Ulrich: