Thorin Oakenshield vs Thorin Stonehelm is this the same character but somehow his name it's changed ? Can we use both heroes in the same deck ?

The rule is you cannot use 2 unique characters with the same name. They haven't the same name, so I don't see you couldn't do this.

I don't think it is the same character with a different name, it would be a bit strange...

Thank you!

Since they don't have the same name, you can use them together.

Also, they're not the same character. Thorin Stonehelm was Dain's son, who became King Under the Mountain after Dain died at the end of the War of the Ring.

In case you revisit this confusion, Bard the Bowman and Bard Son of Brand are also not the same character - the latter is the great grandson of the former.

Thorin III Stonehelm's great-great-grandfather was Dáin I, who also was the great-grandfather of Thorin II Oakenshield, so both Thorins are second cousins once removed.

Thank you!

man I thought this was going to be "who would win in a fight"

it's totally Stonehelm