Hafþór Júlíus Björnsson, the hulking Icelandic strong man who plays The Mountain on Game of Thrones, has revealed his training partner — a tiny Pomeranian named Asterix.

Yes, that’s right — when he’s not crushing skulls in Westeros, The Mountain takes care of this adorable little guy.

The Mountain

Instagram / @asterix_astrikur

Björnsson, who has won the title of Europe’s strongest man two years in a row, is roughly 66 times heavier than Asterix, but that doesn’t stop them from training together. In fact, Björnsson calls his runs with Asterix “the most intense cardio I’ve done in years”.

The Mountain

Instagram / @thorbjornsson

The Mountain

Instagram / @thorbjornsson

The Mountain

Instagram / @thorbjornsson

Björnsson, who was a professional basketball player before finding fame as a strongman and actor, has played The Mountain — aka Ser Gregor Clegane — for the last three seasons of Game of Thrones.

The Mountain

Instagram / @asterix_astrikur

The Mountain

Instagram / @asterix_astrikur

The Mountain

Instagram / @asterix_astrikur

We’re just glad Asterix isn’t a character on the show, because we’d hate for George RR Martin to kill off this little bundle of furry joy.

Is your pet a good training partner? Let us know in the comments below!