Metallica frontman James Hetfield turned 51 yesterday (Aug. 3), and he received a warm greeting from none other than Megadeth mastermind Dave Mustaine! Despite their past differences, Mustaine wished Hetfield a happy birthday, adding, "We changed the world brother!"

Ever since Mustaine was kicked out of Metallica in 1983 for drug and alcohol abuse along with violent behavior, tension between Metallica and Dave Mustaine has been documented comprehensively. However, in the past few years, the two parties have been burying the hatchet. Metallica shared the stage with Megadeth during an iconic handful of 'Big 4' dates that also featured Slayer and Anthrax, and Mustaine even participated in Metallica's 30th anniversary celebration.

In celebration of Hetfield's 51st birthday, Dave Mustaine sent out a heartfelt tweet to his longtime brother in thrash:

In other Megadeth news, the band has been posting clips from multiple festivals throughout Europe and Russia. Check out Megadeth's Facebook page for a bunch of awesome videos. Metallica, meanwhile, will play their last scheduled date of 2014 at this coming weekend's Heavy Montreal festival.

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