Shamrock likely only exists so that Luffy can defeat Shanks without actually fighting him.
Hence I think it’s quite likely Shamrock knows how to use divine departure and Shanks’s other moves.
We know Shanks once went to live in mariejois temporarily. My guess is when he did that, he probably sparred with Shamrock. In the years since, Shamrock copied and mastered all of Roger’s moves that Shanks had learned and showed him in their sparring.
Ultimately Oda has used Luffy’s rivals to hype up his future opponents in the past. Law lost to Doffy, then Luffy beat him. Kid lost to Kaido, then Luffy beat him.
I think Shanks vs Kid could have also served to hype up Shamrock if Shamrock also has divine departure and the rest of Roger’s arsenal.
Ultimately, Luffy vs Shamrock might not just be a stand in for Luffy vs Shanks. It could be an opportunity for Luffy to face the shadow of Roger himself.
Hence I think it’s quite likely Shamrock knows how to use divine departure and Shanks’s other moves.
We know Shanks once went to live in mariejois temporarily. My guess is when he did that, he probably sparred with Shamrock. In the years since, Shamrock copied and mastered all of Roger’s moves that Shanks had learned and showed him in their sparring.
Ultimately Oda has used Luffy’s rivals to hype up his future opponents in the past. Law lost to Doffy, then Luffy beat him. Kid lost to Kaido, then Luffy beat him.
I think Shanks vs Kid could have also served to hype up Shamrock if Shamrock also has divine departure and the rest of Roger’s arsenal.
Ultimately, Luffy vs Shamrock might not just be a stand in for Luffy vs Shanks. It could be an opportunity for Luffy to face the shadow of Roger himself.