'Thrones' Star Jason Momoa Scaring Everybody With Maori War Dance

EXCLUSIVE

Jason Momoa
's character was killed off "Game of Thrones" WAY before it became trendy ... but he's keeping up with one CRAZY-INTENSE cultural tradition that would make even a Dothraki warlord quake in his sandals.

Check out Khal Drogo (middle) doing the "Haka" -- the traditional ancestral war dance of the indigenous Māori people -- at the beach in Auckland, New Zealand on Sunday.

Momoa hails from Hawaii but says he's obsessed with Polynesian culture ... he even did the Haka dance -- in character -- as part of his GoT audition.

Momoa's no hack at the Haka ... but if you want to see something REALLY scary, check out the New Zealand national rugby union team -- which performs the dance to scare the crap out of opponents before matches.

Not pictured: whatever's running down the other team's legs.